FN was heavily promoting their new 509 pistol at NRAAM. The 509 is a striker-fired 9mm pistol with an MSRP of $649.00
The stippling molded into the grip is very aggressive, almost painfully so. It is not going to slip out of your grip, but keep on gripping it hard long enough and it may make you wish it did.
Yes, the rear of the slide looks very Glock-like indeed. Meanwhile the trigger looks somewhat like an M&P with the smooth jointed trigger face and had a better feel than a Glock.
17 rounds of 9mm in standard capacity, changeable backstraps, ambidextrous magazine release, and very nice solid sights - either luminescent or tritium - come on it, and a mil standard rail is molded on the frame. The FN 509 weighs 26.9 oz.
The 509 was FN's entry into the Army's Modular Handgun Competition and apparently had over a million rounds of testing so it's likely had all possible bugs worked out of it.
It's not a bad choice for a full sized striker-fired handgun, but it's a newcomer in a market teeming with full-sized striker-fired handguns.