Wow the E-Grip is awesome! It is very fast and combined with the loudness of the A-5 that makes a machine gun like sound. The four fire modes are convenient all work great. The turbo-response mode is particularly useful for me. All fire rates can be adjusted when in each mode by use of the adjustment screw. The trigger pull is short and fairly light - a huge plus. The E-Grip is tournament legal too (unlike the RT). One downside is the high price, but nothing can so easily make an A-5 into a very fast gun. The best upgrade I have made for my A-5 and it's just great!
I highly recommend the E-Grip; it turns any A-5 into a formidable marker.