Pros:
My favorite polymer striker handgun behind my Walther PPS M2. I like the straight backstrap and mine came with the curved one as well. Accurate, reliable to the point of being boring with everything I have fed it, which is a good thing. WWB and four different brands and weights of defensive ammo to the tune of 400rds through mine without a hiccup. Midwest Gun Works has a nice stock of OEM parts if you want to put together a kit for it.
ETA: I forgot to mention the aggressive texturing on the grip. Excellent stick-to-it-ivness.
Cons:
Made by FN, which has a history of making a good gun and then dumping it for the next model. Not much aftermarket for it (Does not need any for me). Mags are expensive, best I could find online was $38 per. I picked up two extra, good thing it came with three. Oh yeah, the recall. Have not sent mine in yet, but I will.
I take mine to the range every time I go now, and I see no change in that habit coming. I spent a bit over $100 with MGW getting replacement springs for all my mags, a extra extractor, recoil spring assy and pretty much all the small springs in the gun. I think I have about $600 in this all told and I already find it to be worth the money. I have had a Springfield XD that was "meh", a SAR B6c that is pretty good and will make a great "truck gun", and I have tried Glocks which I can't stand. This FNS 9 is going to be my nightstand gun with a TLR-1 on it.