Aine, I use D'Addario phosphor bronze light gauge, 12-53. Funnily enough, an hour after replying to the thread,I broke a first string! It snapped at the machine head, so I'll check that there aren't any sharp edges there before I replace it. They've lasted since Xmas so I can't grumble. Generally, I use standard tuning, with dropped D fairly often, so I can understand that players who are constantly altering their tunings may have more problems. To follow up the point about Wavy frets and the intonation irregularities they are attempting to rectify, for most guitar players the worry is the the tendency for certain chords to sound wrong even after careful tuning. I have a hunch that this may be due to an overdependance on electronic tuners. I always make minor adjustments by ear after tuning. Dave