Natit, ATIinject, and Titan are all injectors, they serve the same purpose but sometimes they work for different cards and different versions of OS X. Well if 7.5.5 is slow, then I think you can revert back by installing QuickTime 7.5.4 over it, correct? I'd love to give you the drivers but unfortunately bhast2 said that he'd be making the packages for the ATi Drivers and I haven't been able to get in contact with him for a few days leaving this project at a complete standstill