Having bought and sold at least a dozen block grinders I am still not impressed. Amps is only one of two very important criteria. The other is weight. A light weight grinder will be more susceptible to vibration if the wheels are not perfect. Of the three brands mentioned, the only one I would buy is the Dayton. I'll admit though, I've never played with a Dewalt. I had a Delta 8" for a while. It was OK but nothing special. I sold it very quickly after I stumbled on a Wissota 7". Make sure you have a way to true the wheels and keep them that way. Diamond dressers have become really reasonable and my preference over the traditional wheel type.