FN Herstal is not new to the ambidextrous pistol line. The FNX and the FNS preceded the 509 line with very well designed controls. While the FNX had all the bells and whistles including a threaded barrel and a red dot cutout, the FNS did not.
That has been solved with the 509 line of pistols. They begin with the standard 509 that is similar to the FNS. It has similar ergonomics, and I believe they’ve beefed up the slide stop lever.
The 509 Tactical is the pistol that I own. It is like the FNX’s little brother. The ergonomics are great. No thumbnastics is required for operating the mag release, and the ambidextrous slide stop is great. I’ve not had a pistol that I can run the slide left handed with out racking the slide, and with the addition of the Red Dot, It’s quite nice and quick.
I’ve installed a Trijicon RMR on mine, and it co-witnesses nicely with the suppressor height Trijicon night sights. If you are not running a red dot, the factory installed rear sight wings are a nice addition to protecting the already robust rear sights.
What’s crazy about this pistols is that it holds 17+1 9mm round nicely with the included standard magazine. But it also comes with two more 24 round extended magazine. They are the same height as the slide, so if you are carrying concealed, a custom holster will marry the two up nicely, with out too much bulk.
Throw on a suppressor, weapon light, extended mag, and red dot sight, and you have quite the outfitted pistol.
I’ve now run nearly 1000 rounds through this pistol in all configurations, and it runs great. It’s eating up my hand loads, and has no problem with Speer Gold Dot 147s.