This is what I have as far as Track:
505T- Very strong ball for the long/heavy oil
916AT- My benchmark ball for league, strong backend
920T- My 2nd benchmark ball for league/tournament, very smooth midlane but can be somewhat angular with added polish
715C- Smooth arc for medium oil, find it better when it's dull at 2000.
607A-Length and angular on the backend (might replace 715C and 607A with the new 718A).
505C- Long and smooth arc for broken down shots and short oil