For my actions, I like the 1 piece picatinney setup better. You have a large variety of rings to choose from for one big thing. The other is the alignment of front to rear is always right. The dovetail blocks are a little tougher to get exactly right. In the end, I think the pic rail is the easiest option, especially for the guy who just buys one and puts it on himself. My action have alignment pins in addition to the screw holes, so it's hard to not put it on right.