Great strings, been using them every day for around a week now and they still feel like new. most strings start to darken both visually and audibly after this amount of time so was pleasantly surprised.
Sound-wise, other than staying brighter for longer, I don't think there's a huge difference in sound.
overall 4 stars, rather than five as they're pretty much twice the price of a regular pack of strings, but not necessarily twice as good. Great strings, but I think if you change them regularly anyway, you wouldn't really gain much for the extra £££'s you spend.