I've no clue about "best". My father used one-piece bases on his rifles. I've always used two-piece.
I put a set of Conetrols on my Sako .243, mostly because they're purtier.
And the rifle's aesthetically pleasing, to begin with. Hey, they work. I needed three hands, though, the first time I went to install them.
I've used Weaver mounts and rings since 1950. I've never had anything bad happen, except once on a Model 100 when I didn't tighten the knobs quite enough. My fault. But there have been some 4,000 rounds of '06 gone past the aluminum bases on my Ol' Pet since 1971. Seems like a fair test.
I don't see how the three little screws of a one-piece base can do much to stiffen an action. The four screws of a two-piece system have 1/3 more strength in shear to resist recoil, if recoil is a factor. Just off the cuff, it seems like the scope tube would do more stiffening with four screws than a one-piece mount with three. Dangfino. Never worried about it.
I recently searched through my wild animal box and found a set of Leupold rings with the horizontal adjustment deal. They're a bit high, but now the scope doesn't touch the barrel.
An old Model 70 in .220 Swift. Gotta go sight it in.
Just some FWIW stuff...
Art