hey pete. to answer your two questions - Yaes and Yes.

i have the GTX and it has 7 different settings for the throtle.
1 is for 540 racing or stock on a tight track where you want acceleration.

then the 6th and 7th settings are for a large track for mod where you want good top speed but conserve your batteries.

i don't know much about the Q2 but i'm sure it has the same sort of programing.

and i think if you were going for the GTX or Q2 i would go for the GTX simply because 1. it is cheaper 2. it is easy to set up and 3. it dosen't have the history which the Q2 has of blowing up.