I've used two part epoxys on concrete floors for 27 years now at work. We apply it on container storage area floors for hazardous material storage, and Ive also used it at home. The Sherwin Williams is pretty good, but I much prefer Anchor (Anchor Hi-build in grey). It goes down and stays down better than anything else we've applied. I put in in my shop on a broom finished floor. After etching, it's lasted well for 6 years now. The only thing I'd warn you about coating over a rough finished floor is that you don't want to get road salts on it (from snow build up on a car). This wreaks havoc on any concrete coating including epoxy. It makes its way in the tiny nooks (a broom finish has way more chances to have these tiny voids) and will soften the top surface of the floor and start breaking up. If you don't have that issue- there is no reason to grind a rough finish down as two or three coats of epoxy will build higher and smooth out the floor enough that it's easy to broom it off. I simply let the mixed two part sit for an extra few minutes before applying, and it goes down a little heavier and builds faster. I've driven in my shop on 100 degree days when the road tar is sticking to my tires, but never had any "hot tire lift" on my floor.
You won't be sorry. Spend a little extra time in the prep, and you'll have a floor that is way easier to clean, and looks a lot nicer as well.