Actually I'm just a part-time, rhythm-mandolin player.
Actually I only wanted to try these because, to me, bronze or silver feels and sounds too abrasive and brash. Besides, I'm familiar with flats on jazz guitar, bass, etc.
With these strings I get a mellow, even tone between the wound and plain strings and they are smooth to the touch.
I would argue that these strings are an upgrade for any mandolin or mandolin player. They even really reawakened my interest in the instrument and in becoming a better player. But that's just me - actually not a full-time mandolin player.
The only negative thing is that the tension seems high for the gauge. I had to do some adjustments to the bridge position and height. But now, even the intonation seems to be better.
In the end, it's probably a question of taste. Nonetheless, definitely worth trying.