INSANE ROF, 900rpm=15rps, don't have to replace batteries.
Tendency to use a lot of paint, not allowed in some tourneys.
My first impression of this was, WHOAH. a simple squeeze of the trigger and I had rattled off about 5 rounds. I was impressed. easily capable of full auto, which is good for me in the scenario games i like to play. Those who say it makes your gun a "gas hog" are incorrect. It appears to because you are shooting a lot faster than normal, but the gun gets the same amount of shots from a Co2 bottle. It only uses EXCESS gas to reset the piston behind the trigger. The gun itself(a-5) is a gas hog, (about 500 shots from a 9-ounce bottle!) but, where I play, I get free air refills all day for $10, so not really a big deal to me, anyways.
I would reccomend this product to anyone who plays scenario-type games, and has easy access to paint and air refills. Worth every penny IMHO. Does excactly what it says it will do(with Co2, which is what Tippmann designs most of their guns to run off of..)which is why I give it a perfect 10.