I have the 20v xr grinder, it's great lots of power I can get about 15 minutes of runtime with a flexvolt battery, the paddle switch can be a little finicky, but as long as you don't need the bigger wheel and have extra batteries it's a beast, if you think you will need the larger wheel on the flexvolt get it I don't have it but have used it before and it has balls Sent from my Nexus 6 using Tapatalk