I have a cheap Strat copy strung with these and it's great for retro distortion tones, Buddy Holly imitations and more. It can do the hyper-mellow jazz thing too. And for slides? Really smooth. Not so much a benders string, but there's lots of interesting things going on with these. Voicing of conventional chord shapes seem to take on a sense of 2 separate registers, with the unwound strings sounding separate from the chunky, woody sound of the flats. This makes soloing a very different experience, as moving strictly vertically on the neck can have a very abrupt effect (which can be used, to make little call and response or pedal-note style ideas on the fly).
I think anyone who uses round wound, regardless of genre, should try a set of flat wound strings at least once and I'm glad I chose this set.