Tested on a first series Yamaha TRB, after over twenty years of EXL170. Compared to the latter they have a warmer and darker sound, the highs are never sharp even when newly assembled, but they do not lose definition and crunch over the entire range. Rigid enough, without tiring, they allow a low action and, if "stimulated", they roar with a fabulous growl, while played gently they are perfect for blending into the mix even in the most refined jazz harmonies. Finally the C string does not sound clear and "guitar-like". Decent durability, at least two months of intense use. They are worth the little extra money over the EXL version.