KWA if you want to run a gun stock and out preform pretty much anything else stock. Its 11.1 v lipo ready (comes with a certificate) as it comes stock with 9mm heat treated gears and bearings. Thing will take a shit kicking without you having to open it up to upgrade or do repairs for a long time. I have had G&Ps, ICS, G&Gs and my KWA sr10 outperforms all of them
It has also been my most reliable gun ive ever had. It has still never been opened up to be repaired.
You get what you pay for in airsoft.
KWA= reliable performance - stock out of the box