I like my flex, but I did have trouble with it after very little use. The brushes started arcing and it was jerking on and off, rather than running smoothly. I took it apart and ran a commutator stone on the comm.. It has been fine ever since. Of course, it was just out of warranty when this happened. I called Flex, and they wouldn't do anything, even though it was only about a month out of warranty.
I don't know if I'd buy another one. It is nice to use aside from the gear box getting so hot. That isn't a really big deal, but what happened to my motor and the company's lack of support is a concern.