I am not a novice guitar technician. I am 51 years old and have been changing strings since I was 14, and professionally since 2004. While I recommend D’Addario to most of my clients, I occasionally try top-tier strings to test the waters.
Immediately after installing these, the high E string broke while stretching. In all my years of experience, this has never happened to me—not even with budget brands. The fact that it happened with these strings is unbelievable. While one could argue it was just a "lemon," at this price point, it is unacceptable. To be honest, I am so frustrated by this that I will be contacting both Thomann and Thomastik directly.