Kind of a pita to remove spark plugs for a compression test on a hot engine, plus it's been said hot, or cold you don't get the same readings as at room temp. I've always taken a compression reading at room temp, even on my snowmobile, marine, and bike engines. Its nice to have base line to go by when these engines are fresh/new.
You need to take into account that these high mileage engines have carboned up piston tops that will read compression higher than they should be. It's why I like to hit them with sea foam before testing. Let the smoke show begin!