Don't do it -- Tesla dropped the AP/FSD price to trick the last few v8 holdouts into tapping the "Install" button.
BTW, I've been on v9 since the roll out and have almost forgotten Tesla once had a good UI for the Model S/X, so it doesn't seem like it sucks as bad as it did last year
v7 holdout here. Wish I was still on v6, but it crashed hard and they couldn't get it rebooted without updating to v7. :-(
Tesla's appalling software incompetence probably means I'll have to get rid of the car when the extended warranty expires, if something breaks and they can't fix it without updating to vGarbage. (If the warranty's still in effect, I'll sue 'em and make 'em put the old software back on.) Very sad, I wanted to keep the car forever.