I've used this with accurate feeds and speeds like the comparable ONSRUD bit I use all the time. This thing snipped 8 minutes out of 20+ minutes and ruined about $190 worth of material. I thought I would save a few bucks but it ended up costing 10 times more than a decent racquet. Don't skimp on cheap Chinese beats, these are terrible and will really spoil your day. Run away from this patch as fast as you can.