Currently: GHS stainless on my Steinberger, Thomastik Jazz flats on my Metro Jazz 5, D'Addario XL's on my 6, and GHS Nylon Tapes on my p-bass. Next change on the Metro will go back to Chromes, the Thomastik's are a little lower tension than I would like.
As a pro repairman/luthier I have changed thousands of sets of strings over the last 25 or so years so I have been able to check out many set of strings. D'addario, GHS, and Ernie Ball are all pretty consistent. And I have probably strung more basses with these brands. I have found DR to be a bit inconsistent, but the people who like them sure seem to like them a lot. The issues I have seen are strings that won't intonate well right out of the package, or I get a call like "I just changed my strings and the (choose string here) is buzzing like crazy. Usually they bring it in and the buzzing is accompanied by an overtone that is out of tune with the fundamental pitch of the string. Put on a new string and all the problems go away.
-m