When your monitor refresh rate is 60 hz, any variation in framerate above that limit will be evened out at vertical sync. If you don't use vertical sync then microstutter will be the least of your concerns - you'll get horrific screen tearing instead. Below it, it depends on the person whether you notice microstutter at all and if you do, at what framerate. Some never notice microstutter, others are more acute to it. I'd file it inder "Minor Issues - Forget".