When I move back to PA (currently active duty Army) I'm going to start purchasing NFA items. I've held off thus far because I've been moving around a lot. For my first NFA firearm I'd like to purchase a belt fed. From everything I see the only "somewhat" affordable route to get into a 5.56 belt fed is to pick up a DIAS/LL/RR M-16 and then find a Shrike upper. I don't really have much of a desire for a 5.56 belt fed though. I'm definitely wanting a 7.62mm. This purchase will be a few years out but I'm considering getting a semi HK-21 now and then picking up a sear pack when I get back to PA. I'm pretty familiar with the M60 but don't want to spend +/- 25K right up front. With the HK I can get the rifle and then the sear pack...spreading out the spending and keeping my wife from killing me before I get one round down range. My question is are there any HK-21 owners here and how well do they hold up over time. I know they're typically more accurate than other GPMG's because they fire from a closed bolt, but have you had any issues with cookoffs? What are some higher wear parts I should purchase as spares? Any help is appreciated. Thanks,

CMS