RE: WHICH ONE
I have the ST and you can see on xtm.globalhobby.com (the forums) how well the members' ST's have come through. You could even think about getting the Mammoth ST Pro, but the regular ST has many custom upgrades and hop-ups. Go on XTM's forums if you're interested in getting the ST. Or you can ask me questions and ill answer to the best of my ability.