M1A.
Much better balance and ergos, at least as accurate and reliable as the PTR-91, and by most accounts, less felt recoil. The M1A also has a better trigger and better sights.
I have an M1A Loaded. For general use, I wish I had gone with the Scout, but that is my only complaint, and it's a minor one. I am very satisfied with this rifle. It has been very reliable, shoots 2 MOA or better with iron sights and the cheapest ball ammo I can find, and hovers around half that with match ammo.
The best part of the M1A, however, aren't quantifiable. The M1A is a pleasure to own and shoot. It represents the last of the wood and steel battle rifles and comes from a lineage of such fine American rifles, all known for their reliability, durability, and exceptional accuracy and range. Like the M1903 and M1 Garand before it, the M14/M1A is a rifleman's rifle, built by and for riflemen and proven on both the firing line, and the battlefield. And no matter what variant you get, this bloodline is apparent. There is a reason these rifles remain popular in this country despite the rifle's short service life as a standard issue rifle--no other rifle I've ever shot, including my bro's AR-50, the M2, M240, or M249 is as satisfying for me as my M1A--and apparently, a bunch of others feel the same way.
Make mine an M1A.