I think it's going to be a question of your intended use for the gun. A pf-9 is great for it's intended role, a highly concealable gun that packs a larger caliber than usual for that size. It's not a good choice for a range gun or home defense when compared to a Glock 26.
Personally I go with a Keltec p3at as a pocket gun with A G26 as a carry,home defense, range gun. It is a transformer and can go from subcompact/compact/full size with a magazine change. It gives me my defensive shooting practice 99% of the time with the same gun, trigger, sights and point of impact and just use my KT to stay proficient. I also doesn't mess up my other handguns with slide wear and dings.
A Glock 26 also fits my hand nicest of all the models and with the double spring system it's recoil is very pleasant. I'll shoot it all day long and be good out to the 25 yard lane. They are accurate to farther out but that is the farthest my range goes.
To summarize, if it's going to be your only gun then get the Glock but if you already have a suitable carry/range gun then the pf-9 is good for concealed carry. If you don't mind used then you could do both. Granted I got mine before the election craze(Sep. 08) but I was able to find a trade in G26 and P3AT for about $625 total. Both were in great shape.