so i needed to do some concrete grinding , I've never done this before in my life..took my self down to the big box store near me to get a diamond grinding wheel for my new grinder..thats when i grabbed my trusty old movie device and checked amazon..as usual much better price and although i have not used a big box store grinding wheel .this whirlwind works great .ive used it extensively and it has not show much sigh of wear..as i don't have much experience with using this type tool and being female it can get a little intimidating , it spins so quickly..the thing that i like is it seems to be well balanced. my next door neighbor came over and gave me a hand and did some grinding for me..he thought it was a super expensive diamond grinding wheel..i let him know about another one of my great amazon purchase !