Hello,

I have my MacBook Pro M1 Max connected via USB-C and my Mac Pro 2019 connected via DisplayPort (monitor) --> USB-C (Mac Pro).
I can switch between the two Macs by switching my input from USB-C to DisplayPort. Funnily enough, I currently have two setups with Magic Keyboard and Trackpad, as my Mac Pro already had its own setup in the studio. So I don't have to constantly redo the Bluetooth pairing, which would be annoying (otherwise the quickest way to switch is with a short cable connection: then the device is automatically recognised. The cable can be removed afterwards).

Monitor delivers 100W, which is more than sufficient for work/charging. The power is not as high as with the supplied charger, but there it is more about FAST charging.

I mostly drive with MacBook Pro closed in a BookArc, but open in 'dual monitor mode' works fine too.

I have my monitor configured as USB-C priority "High Speed", not "High Resolution", so that I get USB 3 speeds via the other USB ports on the monitor. Otherwise it will be USB 2.
2560x1440@60 Hz looks very good. It's the same resolution as the 27" iMac 5K, only scaled from UHD and not 5K (which is no problem at all).

I had a Mac Pro 2019, an iMac 2020 and a MacBook Pro 16" 2019. Now I sold iMac and the "old" MacBook Pro and replaced it with the new M1 Max + monitor. A very successful change!