I've had the 16-inch M1 Max for 9 months now and working on this device has been a true pleasure every day so far. Sharing my experience below.
I traded in my Macbook Pro 2015 which lasted me 7 years (I'd say one of the best laptops Apple ever made). Apple still gave me $480 for it, and I hope to resell or trade the M1 Max for a significant amount as well at some point (hopefully after at least 7 years of use). It was still functioning very well but simply returned it because my work had new hardware requirements.
The only reason I might trade it in is if high-res color eInk laptop displays with at least 120hz become available at some point, but I don't see that happening in the next 5-10 years.
64GB RAM
I often work with large datasets, which is why I went for the 64GB RAM M1 Max (and 4 TB).
With 64GB of RAM it's very nice to work with (samples) of most datasets locally before sending off code to the university's cloud computers (which are not always available). I often have quite some datasets in memory at the same time, and the M1 Max CPU slices through them at light speed. Also need the RAM for all kinds of things that you wouldn't expect at first but can eat up surprising amounts of memory (e.g. if I have Python, R and .lua files open, their corresponding language servers for autocomplete functionality and so on can already take up some gigs of ram).
3 4K External monitors (1 is 120hz)
Also went for the M1 Max because it can support up to 4 external monitors whereas the M1 Pro can only do 2. Across these I often have have at least 7 windows open (2 code windows, 2 REPL windows (Python / R), a terminal, browser with documentation, often a LaTeX document, the corresponding paper in .pdf, e-mail, and so on.).
16 inch vs 14 inch
Went for 16" rather than 14" because I like to work away from my desk 1 or 2 days a week, e.g. in the libraries on campus, and I often have at least 2 windows open which fit just fine next to each other on the 16". I have no problems carrying it around on campus all day, don't really notice the weight in my backpack give 2 pounds more or less. I'm using an older iPad as second monitor on-the-go (through Sidecar) which works flawlessly as well.
Python, R. etc.
I mostly work with Python, and sometimes R and STATA and lua, and all libraries that I use often run natively on the M1 now (at launch 9 months ago I'd say this was about 70%)
Linux laptops
I've also tried different laptops with Linux for a year but was often babysitting these laptops with recurring hardware / software problems (deep sleep, crashes, battery, printing, connecting multiple monitors with the right resolutions etc.). Instead I haven't rebooted the M1 Max for weeks, everything just works.
I am excited though about the development of Asahi Linux on the M1 which has developed rapidly the past year, once the GPU and Thunderbolt ports work I'll definitely give that a try and put a Linux clone on my device with the same files (also one of the reasons I got a 4TB SSD is to experiment with these kind of things).
Applecare / rental insurance
I have Applecare+ for it and also rental insurance in case it gets stolen. Apple really gives you peace of mind. I had a Dell laptop for a while and paid for next-day on-site repair, but Dell doesn't tell you that that applies only if they have the part that's broken is in stock (in my case the trackpad was not in stock and I'd have to wait for weeks / months). With Apple focusing on just a few core devices you know they'll be able to repair it no matter what.
Gaming
Also was nice to see that some AAA games released this year, such as Total War: Warhammer 3 (runs natively) and God Of War (through CrossOver) run pretty well according to my standards (60 FPS at least on high settings).
Other
Also want to re-iterate the amazing battery life (can go on for at least 8 hours with data analysis / paper writing in conjunction e.g. remotely in the library), wonderful high-res 120hz screen, build quality, trackpad, keyboard (!) and so on.
Cost
My view is, if your livelihood depends on it and you spend > 8 hours every day on your laptop, it's one of the few things you shouldn't skimp on. Opt for a trade-in: with my trade-in Apple paid me 1/3 of the original price of my Macbook Pro 2015 after almost 7 years of daily usage, very reasonable I'd say (on eBay / my local Facebook marketplace it tends to sell for the same amount or even slightly higher).
I traded in my Macbook Pro 2015 which lasted me 7 years (I'd say one of the best laptops Apple ever made). Apple still gave me $480 for it, and I hope to resell or trade the M1 Max for a significant amount as well at some point (hopefully after at least 7 years of use). It was still functioning very well but simply returned it because my work had new hardware requirements.
The only reason I might trade it in is if high-res color eInk laptop displays with at least 120hz become available at some point, but I don't see that happening in the next 5-10 years.
64GB RAM
I often work with large datasets, which is why I went for the 64GB RAM M1 Max (and 4 TB).
With 64GB of RAM it's very nice to work with (samples) of most datasets locally before sending off code to the university's cloud computers (which are not always available). I often have quite some datasets in memory at the same time, and the M1 Max CPU slices through them at light speed. Also need the RAM for all kinds of things that you wouldn't expect at first but can eat up surprising amounts of memory (e.g. if I have Python, R and .lua files open, their corresponding language servers for autocomplete functionality and so on can already take up some gigs of ram).
3 4K External monitors (1 is 120hz)
Also went for the M1 Max because it can support up to 4 external monitors whereas the M1 Pro can only do 2. Across these I often have have at least 7 windows open (2 code windows, 2 REPL windows (Python / R), a terminal, browser with documentation, often a LaTeX document, the corresponding paper in .pdf, e-mail, and so on.).
16 inch vs 14 inch
Went for 16" rather than 14" because I like to work away from my desk 1 or 2 days a week, e.g. in the libraries on campus, and I often have at least 2 windows open which fit just fine next to each other on the 16". I have no problems carrying it around on campus all day, don't really notice the weight in my backpack give 2 pounds more or less. I'm using an older iPad as second monitor on-the-go (through Sidecar) which works flawlessly as well.
Python, R. etc.
I mostly work with Python, and sometimes R and STATA and lua, and all libraries that I use often run natively on the M1 now (at launch 9 months ago I'd say this was about 70%)
Linux laptops
I've also tried different laptops with Linux for a year but was often babysitting these laptops with recurring hardware / software problems (deep sleep, crashes, battery, printing, connecting multiple monitors with the right resolutions etc.). Instead I haven't rebooted the M1 Max for weeks, everything just works.
I am excited though about the development of Asahi Linux on the M1 which has developed rapidly the past year, once the GPU and Thunderbolt ports work I'll definitely give that a try and put a Linux clone on my device with the same files (also one of the reasons I got a 4TB SSD is to experiment with these kind of things).
Applecare / rental insurance
I have Applecare+ for it and also rental insurance in case it gets stolen. Apple really gives you peace of mind. I had a Dell laptop for a while and paid for next-day on-site repair, but Dell doesn't tell you that that applies only if they have the part that's broken is in stock (in my case the trackpad was not in stock and I'd have to wait for weeks / months). With Apple focusing on just a few core devices you know they'll be able to repair it no matter what.
Gaming
Also was nice to see that some AAA games released this year, such as Total War: Warhammer 3 (runs natively) and God Of War (through CrossOver) run pretty well according to my standards (60 FPS at least on high settings).
Other
Also want to re-iterate the amazing battery life (can go on for at least 8 hours with data analysis / paper writing in conjunction e.g. remotely in the library), wonderful high-res 120hz screen, build quality, trackpad, keyboard (!) and so on.
Cost
My view is, if your livelihood depends on it and you spend > 8 hours every day on your laptop, it's one of the few things you shouldn't skimp on. Opt for a trade-in: with my trade-in Apple paid me 1/3 of the original price of my Macbook Pro 2015 after almost 7 years of daily usage, very reasonable I'd say (on eBay / my local Facebook marketplace it tends to sell for the same amount or even slightly higher).