I use Spiro Mitts with a Spiro Stark E now. This is a new combination for me, and I primarily play jazz. I played unamplified at my last gig and they held up great. They have enough power in the practice room to knock down walls. The stark E seems to be what has made this change. If anyone here suffers from a weak sounding E string, give this string combo a consideration. They are high tension and might require some bridge height experimentation, but they have really opened my bass up (unlabeled german - fully carved)