Fresh Install of OS vs Time Machine for New MBP?

[UPBaylor]

I've seen plenty of threads advocating for a fresh install of OS when upgrading computers. Is that really very beneficial now? It seems like the call for fresh OS installs has died down over the years. Perhaps Apple has improved the periodic upgrades to fix most leftover issues?

I have a new 13" MBP on the way to upgrade from my mid-2014 MBP. Everything seems to be running ok on my current machine running the latest Catalina. A fresh, clean OS install adds some effort to the switch over, but I could do it if it's of significant benefit. The current MBP is not heavily loaded down with programs or files. I'd call it moderately loaded, but probably on the lighter side compared to many/most here on this forum. I don't use it for any graphic work, just mainstream computer work. Do you think I would notice any significant improvement with a fresh install or will the Time Machine migration likely be about the same?

And, finally, could I just start with the Time Machine migration and do a fresh install later if desired? Is there any real benefit from doing it from the very beginning of launching a new machine vs later?

Thanks for any advice and opinions!

 

[Boyd01]

I usually just use Migration Assistant when setting up a new computer, but I was still running Sierra on my old Macs, so I did a clean install on my new Mini with Catalina. It was straightforward, but a lot more trouble since all my passwords and settings had to be setup again manually. Was able to import my Safari bookmarks at least. I was not using iCloud passwords at the time, that would have made it easier.

In your case, coming from Catalina, I would probably just use Migration Assistant as part of the standard setup routine and connect the Time Machine disk so all your old settings, passwords, apps and data would be automatically transferred.

Don't really understand the part about "doing a fresh install later". That does not make sense to me, you would have to completely wipe the MBP and manually re-create everything. I'd say you should decide if you want a clean install now, before doing anything else.

 

[Honza1]

What is best depends on what you are willing to do. Even using Migration Assistant, you will move lots of crud to new machine. I know, I used MA few times and recently I discovered kext from ~2012 (2 MBPs ago) which had no use in the new machine I have now. These can cause instabilities and slow down system, take space,...
The cleanest (fastest and most stable) system you achieve by : reformat, install new macOS (Catalina?), manually copy only documents you need, install latest (Catalina compatible) versions of applications you need. You will need to recreate any customizations and have all install sources, serial numbers, passwords,... It is pain to do, but you get cleanest system at the end.
Second option used much easier is to reformat, install new macOS, use Migration Assistant (from TM or any other backup) to move (possibly selectively) account with stuff you will need.
Third option is install simply newer or same version of macOS over existing installation. This can sometimes fix system problems, when they happen - specifically by reinstalling the same version over the system. You should use the full installer here. This is simple but removes no crud.

Now, Apple has been making some stuff incompatible with new versions of macOS (Catalina = 32bit apps), so some crud now gets removed during system upgrades. Some are angry, some happy. Depends. But it helps to get rid of old stuff. Next macOS release should retire old kext versions and require new kext model, again, cleaning some more old crud.
Pick your poison and do what you want. In any case, I strongly suggest you create not only TM backup, but also CarbonCopyCloner backup, bootable, tested, verified. May be two. Just in case drive dies at very wrong moment. Storage is cheap, some data are irreplaceable.

 

[UPBaylor]

What is best depends on what you are willing to do. Even using Migration Assistant, you will move lots of crud to new machine. I know, I used MA few times and recently I discovered kext from ~2012 (2 MBPs ago) which had no use in the new machine I have now. These can cause instabilities and slow down system, take space,...
The cleanest (fastest and most stable) system you achieve by : reformat, install new macOS (Catalina?), manually copy only documents you need, install latest (Catalina compatible) versions of applications you need. You will need to recreate any customizations and have all install sources, serial numbers, passwords,... It is pain to do, but you get cleanest system at the end.
Second option used much easier is to reformat, install new macOS, use Migration Assistant (from TM or any other backup) to move (possibly selectively) account with stuff you will need.
Third option is install simply newer or same version of macOS over existing installation. This can sometimes fix system problems, when they happen - specifically by reinstalling the same version over the system. You should use the full installer here. This is simple but removes no crud.

Now, Apple has been making some stuff incompatible with new versions of macOS (Catalina = 32bit apps), so some crud now gets removed during system upgrades. Some are angry, some happy. Depends. But it helps to get rid of old stuff. Next macOS release should retire old kext versions and require new kext model, again, cleaning some more old crud.
Pick your poison and do what you want. In any case, I strongly suggest you create not only TM backup, but also CarbonCopyCloner backup, bootable, tested, verified. May be two. Just in case drive dies at very wrong moment. Storage is cheap, some data are irreplaceable.

Thanks for all those thoughts. As to your second option, that sounds like the best of all worlds. I didn't know you could use MA for everything except the OS. Any suggestions on where I can go read more about that approach or a way I could do a trial run at getting it ready without actually pushing the final "button"?

I've used MA and CCC in the past, but it's been a long time (6 years) and don't remember much about it specifically. I have a TM backup already that runs on a Time Capsule and I also back up all my data folders via One Drive.

If I have any old junk slowing things down, I don't know about it and again, things appear to be running smoothly. But, I also don't have anything to compare apples to apples.

 

[Apple_Robert]

In my opinion, doing a fresh install on a brand new computer is a waste of time, unless there is some OS related problem occurring.

I would make a backup using CCC and that way, it will make it easier for you to find and move the items you want over to the new machine. I haven’t used MA so I can’t comment on that aspect.

 

[chrfr]

I've seen plenty of threads advocating for a fresh install of OS when upgrading computers. Is that really very beneficial now?

It never was beneficial. Don't waste your time.

 

[Honza1]

Thanks for all those thoughts. As to your second option, that sounds like the best of all worlds. I didn't know you could use MA for everything except the OS. Any suggestions on where I can go read more about that approach or a way I could do a trial run at getting it ready without actually pushing the final "button"?

I've used MA and CCC in the past, but it's been a long time (6 years) and don't remember much about it specifically. I have a TM backup already that runs on a Time Capsule and I also back up all my data folders via One Drive.

Well, I am not sure if there are any instructions, Google may be able to find them. Apple probably has some "how to". But as usually, the idea is that if you need manual, the tool was not written right...
Last time I was using Migration Assistant, I ended up doing it twice - first time I did not move exactly what I needed (I moved too much) and there was some issue with final system. So I wiped again and migrated second time. It worked perfectly. That is good thing - if you have good backup, you have a choice to try it and if needed, redo it. So you learn.
Note, that any backup on network drive (including TimeCapsule) is ridiculously slow to recover from. It seems great idea, it is really bad in real use. Considering cost of USB-3 hard drives (which are pretty cheap...) having local TM (or CCC) disk is lot (I mean LOT) better.