Part of me likes the idea of separating the monitor from the CPU - my late 2015 27" 5K Retina is still gorgeous - the computer itself is less than gorgeous. It is sad that upgrading the computer throws the baby out with the bathwater.
Going with the Studio and the 27" 5K monitor - 5-6 years down the road, I can buy a new 'Studio' and keep my monitor.
This first purchase will be painful $$-wise, but looking to future purchases, kinda makes sense.
Now I have to decide if buying a Max MBP 16 instead of the Studio - using a bluetooth mouse and keyboard - plugging into the 27" monitor - gives me some extra flexibility for maybe another $1k+.
The MB Pro will have its own idiosyncrasies - temperature - but being able to unplug and go has its benefits.