I use whatever strings the store has that are the cheapest. If you're a good musician, it doesn't matter what strings you use, you sound good regardless. If you're a shitty guitar player, it doesn't matter what strings you use, you sound shitty regardless.

As far as the string themselves go, there are only a few string-makers in the business. They make all the strings and then various guitar manufacturers buy them up wholesale and put their own names on them and then peddle them off to you retail.

I'll bet most of the guitarists on this thread who hate a certain brand of string and love another would be shocked to learn that they are the exact same strings made by the same company.