I did the same upgrade, I kept my T500 pedals because they seem a lot better than the standard T-GT 2 pedals.
The T-GT 2 is great, a real upgrade from the t500rs.
I have TGII since a week and I really enjoy it..what setup do you use in GT7, 5-5 seems ok, I tried saturation at 1 after seing this in some post but I quickly came back to 5, perhaps some other settings are better?