I sure see some different opinions on this topic. So here is mine.

I like a one piece base. I believe it makes the action more rigid, which makes the rifle more accurate.

I like the Picatinney style. I think it allows more adjustment for eye relief. And differences in how the shooter shoulder's their rifle.

I think the Weaver "STYLE" ring is the strongest you can get. There is nothing wrong with the Weaver rings and base, as long as you get the good ones. Not the cheaper ones.

Leupold standard set ups are good quality. I just do not like the fact that they are limited in their adjustability(unless you go with their "Weaver" style). And with the Leupoldyou really need to know how to mount your scope, or you can bend your scope very easily. I have seen alot of bent scopes. Tom.