I have some GLocks (34, 20, 19).  I am checking out FNS-9's and trying to decide if I would be better off with the standard FNS-9 or the FNS-9 Long Slide (competition).  Either model I would get the stainless slide and factory night sights.  Would the Long Slide model be the obvious choice for competitions or are there some type of competitions where one would want a standard carry gun?  LIke use the Glock 34 for 3gun and the FNS-9 standard for IDPA?

The trigger on the FNS is nothing special - long and crunchy, definitely not conducive to rapid fire in match conditions (though probably a decent enough carry trigger). Even the prototype "match trigger" I felt recently was just "meh"... nothing like as good as the Apex FSS trigger I run in my M&P9 Pro 5".

For 3-Gun and USPSA matches, the longer sight radius is a benefit. For CCW not so much, though you can get away with it if you use an IWB holster.

One other comment: The safety is not the biggest and not very quick to engage on the clock. Some rules look on this gun the same as a Glock or M&P (DA striker fired) and so the safety is optional, but some matches may require that if a manual safety is installed it must be used. Make sure your local 3-Gun match rules are OK with you abandoning the FNS "off safe".

Even when looking at the 5" version of the FNS, it wouldn't be my first choice. The trigger is not competition friendly as the work to improve the trigger pull is difficult with a lot of parts and polishing only goes so far.

And as mentioned, the safety is too small. If you like the feel of the gun, I would go for the FNX and start hammer down.