I introduced Nort's U.M.M. to my group a few months ago and we've really enjoyed the added versatility it gives to the melee and martial classes. In addition to helping balance melee and martials with magic users, Nort's U.M.M. has also added a lot of flavour and creativity to encounters. It's been really satisfying seeing players using the manuevers to think outside of the box when fighting. It's also made my job easier by giving me a bit of extra flavour to build the narrative of the fights around. Our Half-Orc Barbarian now tumbles out of the way of attacks and gleefully taunts his enemies to invoke their rage, and our Monk thoroughly enjoying tripping unsuspecting opponents and making dramatic grappling attacks.
I started on the basic version but have since purchased the full version and am really pleased with the ongoing updates and refinements. Definitely worth purchasing and supporting Nort and his brilliant work.