Just got an SRU-Precision chassis from Taiwan and fitted it to a VFC M4 GBBR. Powering it with HPA through an adapter. Added a short-stroke bolt group, which is great because the original recoil was distractingly strong. It seems to need higher pressure than expected but I've heard these V3 guns have steel internals so they can take whatever pressure you put through them. Can’t wait to skirmish with it in a fortnight.