I've got various 1911 pistols from Bruni Blank Firers to single shot Airsoft springers. I recently bought the KWC C02 1911 (albeit 4.5mm Steel BB version). It's a top replica of the M1911A1 - the best I've seen and certainly at LESS than £90 you can't go wrong! Better functionality than any blank firer I've got and I'm sure the Airsoft version is pretty similar. Swiss Arms/KWC are rapidly becoming my preffered choice of manufacturer as a collector and I like both steel BB and Airsoft. Here's hoping they produce a GBB C02 Airsoft MP40...
Yes, the KWC is very good, but it shoots 340-400 fps, which is an awful lot for a pistol.
I have a KWC CO2 1911, and its fps is about 330. I have an adjustable floating valve in it - basically an NPAS.
I'm told it's the one made for the System 7 MP7.
I also have the awesome TM M1911A1...