My friend just bought a new pirhana that had the electric trigger set up, so i was a little intimidated by it, semi vs. auto. So i went and looked at prices and the RT was cheaper than E-Grip so thats what i got. It takes a little bit of time to install but not to bad. The thing i love is i can still shoot it Semi, but when my friends are hiding behind a big bush or a tree, all i need to do is squeeze that trigger down and watch the paint fly. Now if that just doesnt make a person feel good when they can tag someone behind a tree, I dont know what would.
Conclusion:
I would definitely look into all the options as far as E-Grip vs. RT, with the RT ive noticed a considerable amount of gas use with it, and thats my own misuse of power, but its definitely a good product.