Stingray, Spyder, Tippmanns and all sorts of other guns.
2 Bushmasters and lots of stuff.
There aren't very many, but chances are if you buy a marker that costs this much you aren't looking to upgrade. Upgrading any low priced marker is pointless once you get to a certain point you could of bought a much better gun. The only thing worth buying is a barrel.
It is a great gun for getting in to the game. It is reliable and doesn't break very easily. Despite what people say, the polymer is pretty durable. It is fairly accurate but could benefit from a new barrel, although I am not sure what threading it is.
So what if it doesn't perform like your Angel. It costs $50.
If you want to get in to the game or don't play very often this is a marker to consider. The way I see it is, you should either buy a marker like this or choke up the money and buy a high performance gun. All the stuff in between isn't worth the money.