I see glad to hear! I originally asked the question because yes I wanted an iPad for note taking but I also wanted one as a second screen for my M1 Mac. Not sure if you have heard but with the upcoming new padOS and macOS there is a feature called universal control, where it allows you to use your mouse/keybord with other devices. So you could move your mouse to your iPad/Mac screen.I highly recommend getting sidecar, it is a game changer if you like to work at coffeeshops, having a dual monitor setup anywhere is AMAZING! I have an M1 air with a 2nd Gen Ipad Pro 12.9 I got used and it works great.
I use sidecar with zoom at the coffeeshop, no battery, for about ~2 or ~3 hours a day, and my battery will drop from ~75% to ~45% in this time.
It can be periodically finicky, especially when all the gadgets are connected (hotspot, airpods) and can drop out. It's not game-breaking though it can be quite annoying if you're on a time crunch (like taking a test).
I noticed today it was at ~10GB of ram, but my Mac didn't slow down or anything, it just seemed weird. If you're wondering if it's worth it, it is!
This feature on paper has benefits over sidecar since it doesn't have to render and transmit an entire second display meaning less network traffic and most importantly significantly better battery life. I've read that sidecar uses 20 - 30 mbps! That is absolutely nuts, a 4k 60 YouTube video only consumes 2 - 3 mbps, that is 10 times as much. I know you can resolve this with a wired connection, but since the iPad will charge too it will drain the Mac flat in no time.
If I were to go the universal control route, I'll splurge a bit and buy the iPad Pro as it has 8GB of ram which is enough for a bunch of safari tabs and multi tasking to run it locally on iPad. Elsewise if I go with just sidecar I don't need that much power and I'd just go with the Air as all the load is on the MacBook. That is why I asked.
Still super impressive that you managed to drop about 10% an hour on a zoom call with a second monitor, sounds a bit off tbh. For me that is my regular battery drain and I have a MBP M1 which has better battery life. On a call about 10 - 15% an hour (depends on brightness) , just web browsing maybe 8 - 10%.
I guess it could go both ways for me since it sounds like you don't have any issues. Thanks!