Before these I had some Gibson strings. I got the Gibsons because they stopped making the Hydrophobics, which I loved, so I figured Gibson must make other good strings. They were ok, but nothing special. Then I saw that D'Addario made a set of XL top and R bottoms. I had to have it. No need to buy two sets and discard half of each now. It sounds and feels perfect, plays like a dream, and stays in tune amazingly long. It hasn't lost its tone yet and I've had the same set in for a long time. Guitars will come and go but these strings are staying. I've found the strings I'll be using for the rest of my life.