Got home from Baton Rouge early yesterday morning and felt pretty good with what I did on my first time in the tournement. GT1 gave me a very good read throughout the tournament. Since I'm more of a straight bowler, I was able to play it straight up the 10 board to about 7-8 and it didn't really jump that hard on the backend even with a slower ball speed. Only time I came across issues with the GT1 is throwing it outside the 7 board (which I didn't do very much) and during transition when everyone was just spraying the oil everywhere.
When I knew it was time to change balls I went to the QZ2 Backdraft and played 15-16 to 8 and it was just beautiful reaction after beautiful reaction. I did polish it before I left for Nationals and I'm glad that I did. Team event I did quite well and doubles/singles wasn't bad but it could have been better expecially with the splits and spare pickups.
I would say the Sigma Hybrid at 2000 grit would be a good choice to have on the fresh oil. But if you get the Thrash I would definitely watch your ball speed because I noticed that ball speed is very sensitive there, expecially with medium oil balls.