RE: Single vs. double scope bases?
A one piece base is held on with three screws where as a two piece base is held in place with four screws. A one piece base gets in the way when loading a bolt action rifle. Two piece bases look much cleaner on the gun than a one piece IMHO.
Weaver/ picitannystyle rings and bases, such as Warne, Leupold Mark4, Badger ord., Night Force, etc...are much much much stronger than Leupold, Redfield, Burristurn in style rings and bases.
IMHO if you want to use Burris rings and bases then use the XTB bases and ZEE rings. But IMHO Warne two piece bases and Warne Maxima rings are what I would use.