CA M15A4 C.Q.B. Upgrades?
 

I am just getting started with airsoft again after taking a long break. So I ordered a CA M15A4 C.Q.B. I was wondering if anyone had some recommendations for upgrades I should get (or experience with this gun) . I know certain guns/brands have a tendency to have weak areas. Like I've read that the M15's RIS can be wobbly, if mine does have that problem is there anyway to fix it? I also did read the Sticky posts in this area, but I would rather have someone help me decide what I should upgrade first and if there are any "critical" upgrades that I would need.

Thanks ahead of time.

CA doesn't have wobbling guns. CA has bad internals (usually pad piston and bucking).

I hope you ordered it in country

Of course ;). I got it from A&A. So what kind of piston/bucking would you recommend?