I've never used this type of string until recently. I'd stuck with roundwound for years. These have a metal core with nylon wrapped around or taped. Because of this wrapping, there is much less string noise.
If you play jazz, blues, or are just looking for a deep mellow sound, this is that the doctor ordered. I also find they are easy on my fingers.
I love the fat, warm tone that these give. They have lasted a long time without losing any of the sound that I love.