Well, I've been playing Trace Elliot strings on my basses (both steel and nickle wound) .045-.105, and .045-.130, but I couldn't get any a while back and I bought a set of Rotosounds and I don't think I'm going back. They have lasted an excetpionally long time and have maintained really great tone.

As for guitar... well, I play GHS, .011-.050, but I'm thinking about throwing heavier strings on my Tele, 'cause it's been living in open d tuning lately. Basicly, my main thought when buying guitar strings has classicly been "ok, how long is it going to take for to break THIS set?"