After using Thomastik-Infelds and occasionally trying out other brands, I must admit that these strings have been the worst experience I've ever had with flatwounds.
When you take the strings out of the packaging, everything seems fine. Everything seems fine even when you are putting the strings on the guitar. That's where all fun ends, because these strings really cannot handle being tuned to the standard pitches. When I use flatwounds, I'm expecting the wound strings to feel as smooth as the unwound strings. That's what you get with my favourite string set, the Thomastik-Infeld .012 flats. These strings don't feel smooth. The winding isn't strong enough for the string to feel stable and they feel like roundwounds after you tune them. The problem is especially bad with the G string.
Sound-wise these are good. Nothing exceptional, but good. They work well with a pickup as well as without one. They give a nice acoustic sound, though quite a lot more bright than the Thomastik-Infelds. The monel surface is oddly similar to the surface on my Rotosound Swing Bass 66 bass strings, which have a stainless steel surface. I personally don't care for it too much, because they limit your ability to play fast, but I guess that's a matter of preference.
Overall, I wouldn't recommend these strings. You will have better luck with Thomastik-Infelds and even D'Addarios. They feel way more stable and the quality is a lot better.
