I don't worry about compression on a small engine. If it fires and runs, that good enough for me. Don't know how you would check it with compression release. I buy most of my small engines new, take care of them and don't have too many problems.
When briggs had 3.5 hp flat heads, I would have problems with exhaust and intake valve seat recession. Had to grind a little off the valve stem.
With overhead valves, I've had about 6 that needed the exhaust valve clearence tightened up.
Have a 20 hp kohler command with hyd valves. No problems at 1200 hours.