As for the Highest quality of gaming, I think you'd be experiencing the best of FF7 with TA's overhaul when they complete it. PRP and other projects are compilations of other mods thrown into one mod with all the compatibility issuse *kind of* fixed lol
TA is basically starting with nothing but the Original FF7 and improving it from scratch, on the install I believe the only Model in the current patch is Barret. I know the hardest part is waiting, but if you spend some time in Team Avalanche's Forum, you can get a general idea of what the improvements are looking like.
TA is a graphical overhaul. Not just of the models, but the menu's, text, battlegrounds, feilds, and so on. Like I said, checking out their forum really helps to see what kind of effort is going into this project.
TA's goal is also to stick to the original as much as possible, which means instead of an Advent Children FF7 experience, You are guaranteed to have the same feel of the entire FF7, with higher quality graphics.
I really hope you head over to TA's forum to look around and see what's in the works.
Their next release will be when they complete the bombing mission (up to the reactor explosion)