I was kind of tough on this one after the first time I handled it, but having owned and shot one for a few weeks now, I've really started to like it. My thoughts are below.
-Barrel sizers = excellent accuracy
-Great efficiency out of the box (I got 25 full velocity shots, next 5 trailed down to 200ish, then gasout 2-3 shots after that. I was shooting fast to get these numbers too, and on a cool evening. I'd imagine 35 decently useable shots isn't out of the question with a lot of time between them on a warm day).
-CO2 Changer has already been upgraded, so if you have any leaking problems (mine did not like cold weather), there is a fix ready for it. I feel the lever could use some type of handle at the bottom near the trigger guard to get a better grip for opening it, but its not terrible as is. I also wish it was a system where the cartridge would just fall out when you open it but the plastic guides inside clip it in so you have to manually pull it out. I'm still playing with them to see if I can get them worked in enough without destroying them (they need to be there to some extent for aligning the cartridge with the seal). Still, its a better system than most "from the factory" ones. Only one better I can think of is the TPX really, but that wasn't perfect either, hard to undue when pressurized without modding or using a tool.
-Ball+Spring detent- almost never wears out, gentler on paint, less drag for better efficiency
-Hands down, the easiest pistol to field strip, EVER.
-Can accommodate a variety of loading systems (springfeed, hopper, ripclip)
-Uses .45 grips.
-Stock grips were uncomfortable IMO
-The grip holds in the very tiny spring and ball for the safety, which can be a little annoying to find if you drop it when you aren't expecting anything like that under the grip.
-Springfeed works, but loading speed is mediocre at best. Can most likely be improved with modding though. (First step should be taking one o-ring off of the plug and greasing it so that its easier to turn).
-Additional barrel inserts appear to only be available with the "Sniper" kit which includes a bottomline setup and mock suppressor. All well and good but I really only want the inserts.
-It's heavy and long, mostly due to the use of full-size internals (not miniaturized/shortened ones like many of the old pistols used)
Overall, while I don't think it is quite as good as my modded out Zeuses, I also have to take into account that those are modded and this is stock. If I compared them stock for stock I'd actually have to give the edge to the SA17, so that says quite a bit. It may not be the greatest pistol but I feel it's a great starting point for beginner pistol players and can be modded to be competitive just as easily as the Zeus can. Plus, you actually have factory support since its new. For the price point, its a great deal, IMO.