I have one.
i am sure i will get corrected, however i think its a bloody bargain. but i have had the slam fire issue that i have now resolved.
in the trigger box there is a tiny spring under the trigger sear, below the piston sear. This spring is too weak .... replace it, job done B)
ASPUK do bits/upgrades for them, aparently they use L96 pistons etc ... gunna be upgrading mine soon™
Edit:- forgot to mention, i am told that they are the same as the snow wolf m24 under the skin(i.e look like a VSR, but arent, ASP style trigger, L96 bolt/cylinder etc)