The PBR and the SPR are fundamentally different rifles for totally different applications.
One has a 20" tapered barrel, the other has a 24" bull barrel. One has a manageable traditionally-shaped hunting stock, the other has a ginormous McMillan A1/A5-style benchrest/sniper stock. One is at home in the woods, the other belongs on a bench. The SPR is going to be a 15-lb rifle by the time you add Badger rings and an appropriate long-range scope, the PBR rig will be 10-lbs with a 3.5-10x40 VXIII. Mine actually weighs less since adding a McMillan Edge stock.
Being an M70 fan, I have both.
Since you specifically asked about the PBR, and subsequently about the M700, I'll tell you that I picked the PBR because it controls the round as it pushes it into the chamber -- i.e. if you hold the rifle on its side while feeding a round, it can't accidentally fall out in the process -- and the safety is a vastly superior design. I don't want to start the old, worn-out M70 vs. M700 debate, so do some searching of your own on Winchesters vs. Remington bolt actions.
My PBR stacks 150gr. Fusions into 0.52" at 100yds very predictably. Your PBR will come with a hammer-forged barrel as well, which is one of the most classic methods for barrel construction.
Best of luck!
Rich