I'm a fan of DR strings for their tone, which seems a bit fuller to me (though I think everyone's impression of a string's tone is distorted by the fact that when you try them out, you're always comparing new strings to old). In the recent past, though, DRs have had occasional reports of bad intonation (I encountered a DR string like that), and I bought one pack that had two G strings and no B string.
I particularly liked DR's DDT ("Drop Down Tuning") strings. Even though I tune to concert pitch, I like the fact that they settle in quickly, with very little stretch-in.
IMO, you can't go wrong with D'Addario. They're solid, dependable and consistent. Many of the strings you can buy in stores or online are rebranded D'Addarios. And for solid strings, there's not a lot of difference between one well-made brand and the rest of them. And it's not unheard of for one string brand to call another, asking to buy, for instance, a couple of thousand .016's to make up for a a stock shortage.