I like the Talley one-piece ring/bases. Properly done, aluminum is more than rugged enough to do the job, and do it well. Cheap, flimsy aluminum rings and bases though are pretty worthless.
I also have had good luck with bases that have the windage adjustment on the rear base. Shooters who follow the directions with these very seldom have any problems with them, and they reduce the amount of adjustment needed on the scope. - You always get the best performance from a scope that is set as near to the center of its adjustment range as possible. This type of mounting system allows that to happen.
Picatinny bases are OK if you like the Weaver-style ring mounting system, and if you do not care what your rifle looks like. There is no way to take the ugly off of a picatinny base, that is just how they are. On some rifles this does not matter but on others, it really does.
The best quality, strongest and best designed rings and bases are also the most attractive. - I am speaking of course about Conetrol rings and bases. Nothing else comes anywhere close to a set of Conetrol 'Custum' rings and bases for a fine hunting firearm.
I use all kinds, but the cheap ones that I have tried have wound up in the junk box before long. It is amazing how much better quality you can get with rings and bases by just spending an extra ten or twenty bucks. If price is not an issue, do yourself a favor and try the Conetrol stuff. - It cost me just under 200 bills to get my BLR set up with them.