I've got a Sig Sauer p226 on order at the moment and tbh all the reviews I have read about them say nothing apart from they are amazing!

.177 bb firing with blow back action and locks back when last bb fired.

Mag slides into the butt which gives it a lot of realism and heft!

Check out the review on youtube.

http://www.youtube.com/watch?v=k8CT6C8vJdc