I own a fal and ptr-91. I also own a saiga-12, and in some respects the 308 and the 12 are comparable. Some personal observations after owning all of them:
Recoil: PTR and FAL both have managable recoil, but PTR has a different kind of recoil feel due to the rollerlock system. The fal's recoil is a bit more typical, and I prefer the ptr's recoil over the fal.
Trigger: FAL trigger is much better, it's lighter & crisper. PTR's trigger is only good after a trigger job. Saiga Trigger is in between, although not as crisp as the fal.
Controls: FAL controls has better ergonomics for right hand folks, especially with bolt hold open. PTR's controls are much more burdensome. As a left handed shooter, I find PTR's controls easier to use.
Cleaning: A lot of people complaining about how difficult it is to clean the PTR, but I find cleaning it only slightly more tedious than cleaning the FAL. Bolt disassembly for PTR is a bit more complex, but beyond that the time it takes between the two is negligible. Saiga can be cleaned much faster and much less frequently.
Accuracy: PTR is slightly more accurate than FAL.
Failures: I've had brass necks break off in the chamber of the PTR in the past, usually limited to certain manufacturers of ammo.