I use only D'Addario strings. There may be better strings out there, but I'm happy with these, so I stick with 'em. My Yamaha SBG1000s wear EJ21 jazz strings .012 - .052. My Washburn A20-CS and my Odyssey V have EXL110 .010 - .046. My bass has light strings on it to make it easier to change back and forth from the six-string guitars. And my acoustics all run 0.12s, again to make the change from electric to acoustic easier.

Effect on tone? Big time! The jazz strings on the SBGs give me a really solid sound. It makes playing clean such a joy, because there's so much rich depth to the tone. The guitars with .010s on them sound good, and I can bend notes, but I've gotta admit that after playing the heavier strings, they seem to be missing something.