It seems a major consensus is that they run as well as anything else with FMJ, and almost always so with JHP stuff. Mine seems to concur. Tweaking the magazine lips is a commonly-suggested fix for issues feeding JHP ammunition.
Otherwise, it's a blowback-operated, single-action, striker-fired pistol with a heavy alloy slide, essentially a huge Raven MP-25, though with a polymer frame instead of an alloy one. They're pretty darn solid and reliable. At one time, they were regarded as a strong value in the budget-gun class, but other options, particularly from Taurus (G-series), have closed the gap quite a bit, sometimes coming down to within $50-70 above the C9's price point.