I have owned this marker since December and it is pretty nice... Only problems: •Co2 may leak out of back and will need to be fixed at your local shop (seems to happen to lots of TPX owners) •Sights are useless (I'd recommend drilling holes in them and filling with white paint or buying a Lapco Front Block and slapping on a red dot) •Stock Barrel will need to be replaced •12 Gram Co2 cartridge will only go through 2 magazines before needing to be replaced. I'd recommend getting the HPA Adapter (installation is crazy) •Trigger pull is a bit heavy
(These are only small problems in my opinion and you may not see them as problems or may never experience them)
Everything else (accuracy, weight, upgrade capability, magazine function, feel, look, holster you can buy) is perfect! I'd recommend this over a T8.1 any day, I can't say if it is better than the SA-17 but my guess would be that it is as well. Also, you can buy first strike kits for these things!