That’s the conundrum isn’t it?
A 20” Compact screams SA, but reality is.. of the typical 6.5, 260, 7-08 or 308 offerings they’re basically tripping over themselves or splitting hairs in reality. They’re that close in terms of speed, ft/lbs and trajectory (ammo being equal across the board mind and 300yrd max range).
Not one of them really excels bar none/hands down over the others. Make a Cal choice and one of those other three just happen to do or offer something that the one you chose can’t do or not well enough and vice et versa.
I’ve legitimately looked at all four Cals ballistic charts extensively over and over and over again.
Yes…even
<gasp> the 6.5CM (I know right?

)
For my requirements - 300yrds and under I’m back to hair splitting and or a rolling of the dice on both Cal choice and setup.