I don't like one piece bases for anything short of an AR15 style platform, and only then if they are quick detach.
The problem you run into w/ once piece bases is adjustment. There isn't any. I'd take the 61 dollars and buy Leupold or Millett rings that are windage adjustable, just in case the rail holes are drilled slightly off on your bbl or your scope has a lower range of adjustment. You could probably get by using a one piece, but if you do have the minor issue of having the rail holes drilled slightly off alignment to the bore, then your scope will be cranked all the way to the left/right, which is highly annoying to me...
It may not bother you in the least. But I definatley would suggest 2pc. Leupolds and save some $$$