On 2000psi you will get about 400 shots, and the gun works just fine with out a trinty im shooting mine with out one (i'll probly get one when i got more money). However with out a triny if you rapaid fire at or over 11bps for every 30 to 50 balls you will chop one(if you fired all 30 to 50 balls with out stoping). You have to have the stock feed feed tube if you want the best proformance. Trust me you'll be just fine. Personaly i dont like the basics of the triny and am waiting for tha Eye to come out, or i may take it into my own hands.
You'll love it trust me i just bought mine and played the frist time with it yesterday. Paintball get so much better