Things I liked: The sheer realism of it, all the fun without going to jail. It has blowback, it has muzzle jump (as a result of the massive slide so really it's just recoil). It's magazine fed and above all it puts a big smile on your face when you shoot it.
Things I would have changed: A larger capacity magazine. It only holds 8 rounds but the mag slide looks to have room if modified to fit two more may mean making a new slide though. Better sights, they are just plain plastic compression fit sights. But they do use a dovetailed base so real handgun sights should fit ... might require some test fitting but they look to be the same as a real desert eagle base. it would have been nice to have a two stage CO2 plug but maybe later versions will have that. And better access to the regulator. This thing is adjustable but only if you can get to it, If you are not mechanicly inclined don't bother with adjustment, it's easy enough for me to get at it ... But I've spent a few good years tearing into rifles, pistols and machine guns as well as paintball markers.
What others should know: It uses .43 Caliber paintballs and the factory set ships at 250fps, it can be tuned up to higher with a 5/32" allen key. You'll need to pull the barrel and slide and the recoil springs are a pain but simple to put back in when you get the hang of it. Adjustment means disassembly, adjustment, assembly, chrono, disassembly, adjustment, assembly, chrono .... you get the idea. Overall it a real blast to shoot and if your field will allow it it's a great sidearm or CQB marker. For just plinking ... it's a hoot as well, just don't expect pellet like accuracy from a paintball, especially if one chops.