After all the negatives about those rifles though, are they still good enough to shoot minute of deer heart at 150-200 yards? Absolutely. "Suck ergonomically" is also a personal opinion, if a gun doesn't fit you they don't fit you, doesn't mean it's the same for everyone.
How many "mil-spec" forged lowers have you broken? I've yet to fubar one, the billet receivers I have are made out of 7075-T6, same as "mil spec" forged lowers and what, if any, metallurgical advantage forged lowers have because the forging process has over the billet, I've yet to need that strength because I've yet to break a lower.
Combined I've seen only 3 "issues" with billet lowers. First run Gen 4 POF lowers wouldn't accept M3 PMAGs because the way they shaped the trigger guard at first, they changed it shortly after. The Jack lower by Spike's Tactical won't accept a 60rd Surefire or a 60rd PMAG drum because of the teeth. And Seekins Precision SP lowers dig into a 60rd Surefire a bit but they still lock in and work.
By nature, and gun can be magazine picky, pistol, rifle, billet, or forged.
Forged lowers, I've seen out of spec pivot pin detent spring cut outs, buffer retainer pin holes being in the wrong spot, **** poor machining leaving burs and then those burs get annodized over (especially around the bolt catch), grip screw holes not being threaded all the way.
