The only things keeping a Ruger out of the same ballpark as the 700PSS is the stock and trigger.
If you get a better stock or properly bed a Ruger (it can be done, and done well), that's half the battle. The biggest problem with them is the funky angled screw setup. Great for a hunting rifle, lousy for a precision gun (unless bedded). Replace that @#$## aluminum trigger guard with a steel one.
Get a Canjar (single-set for extreme range) or Jewell trigger, and the other half of the problem will be solved.
I monkeyed with one a friend carried, and it went from a 1moa gun to a .5moa gun with just the above (and a lil fire lapping). He has shot more than a few .3moa groups, and the rifle holds well at 500yrds (range limit).
Last word----OPTICS!!! Get the best you can, even if it means you can't put as many bells and whistles on the tube as you'd like. The #1 limiting factor of ANY precision system is OPTICS. Again, GO NIGHTFORCE. You will be satisfied, and all your buddies who only got a Leupold will be jealous. Any specific questions, please e-mail me. I've got both rifles and would be more than happy to preach!
In my opinion, the Ruger is a tougher gun. To me, tough is important (my personal precision gun is a homebrew off a VZ24 action).
I would advise improving the scope base/rings, and use a 1-piece weaver-type base with Badger rings. Use GOOD glass (Nightforce all the way, baby!) or everything else is a waste.
The 700 is ok as a base. The big Good Thing about 700s is that people make more goodies than you can imagine for them. There is, in my poor opinion, nothing else that really stands out about them. Adequate action with lots of goodies equals decent rifle. Call the Chandlers at Iron Brigade and let them set you up for a 700.