yup very cool... even better than the marushin cos of the actual use of shells...
However it does make you wonder if any of the manufacturers actually think about practical airsofting when they design stuff... I mean for how long have we been wanting a garrand aeg now!
An AEG cant create the POW POW POW POW effect that gas blowback can create, every1 around can hear my Marushin Garand hammering the rounds out! 
but then also you don't have to run around afterwards looking for enblocs or lost shells!!!
Acutally you can get blow back effect on AEG... the psg-1 is blow back.
yes the PSG-1 is "blowback", but its the worst noise in the world 
I'm sure it would be possible to make the AEG garand's / M14's blowback as the piston is directly below the bolt cover.
If you used the same method as the AK blowback system. By putting a pin thats attatched to the bolt through the top of the gearbox which rests on the back of the piston. Then as you fire the bolt retracts as the piston moves. It is however a bit limp of wrist on the AK. But the M14 bolt will be quiet fantastic if you could pull it off....
....Not that i'm going to cut into the top of my M14 though. But certainly possible.
W3bby: i love the noise my marushin Garnad makes, but its just not good enough for skirmishing with. I might take it with me on sunday jsut to scare the people who haven't heard it yet 
Nick
I have 5 kills with it so far, and 2 at range so I am chuffed.... come the summer you better watch out! hehe! 
lol, i'm on your side............for now
2 at range were flukes I must point out! you know when u blast into a bush just on the edge of the range and some1 walks out with their hand up! 