Our only real complaints is in fact with the damage track. In my opinion, Hit Points were simply replaced by two other less predictable resources: damage ticks on the track and conviction. The reliance on conviction is actually a drawback in my opinion. We found that players horded their conviction because of essentially role they play in combat longevity. So, instead of using conviction to perform dramatic actions with flare and gusto, they were all saved for the crucial toughness save. To a lesser extent, another complaint is with the status effects built into the damage track. My players felt that many of these effects (e.g., stunning) just weren't very fun at the frequency they occurred. Sitting around watching your friends play, while you loose a turn may be realistic, but it isn't very entertaining.
So to paraphase, as a mechanic the damage track holds up well, it just wasn't our cup of tea and didn't promote the style of game we wanted to play (high flamboyant action). In a more gritty game it might perform more to our expectation. Since other portions of True20 do support crazy imaginative maneuvers by the players, we are presently using a True20 hybrid. We've kept the character generation rules, the combat system and the magic system, while simply dumping the damage track.