Two questions I can answer.
I recently had to remove the vararam and return to the stock set up for a California SMOG check- I can't say I'm getting a 25hp gain but definitely noticeable - When I put it back on the next day- could totally feel a better pull.
2. I have zero rub with my 2/3 drop I"m running 22 x 9.5 rims and I am free and clear - even lock to lock.
hope that helps.