Slick Rounds for fretless?

[Heather Kulaga]

I've been using medium taper core KS strings on my 4 string KS fretless forever, and want to make a change. I've tried flat strings on a friend's bass before and just didn't like the feel or the sound at all - felt dead. But I AM looking for something not as bright as the taper core rounds. Something warmer, more thumpy for a new band forming. Are the KS Slick Rounds going to give me something in between taper cores and flats? Also -- should I stay with Medium, since that's what I'm used to? Anybody want to share what they like or dislike about the Slicks? (Or any other recommendations). Thanks!