I've had TI Flats on my P-Bass since the day I got it (currently on its second set). They are a match made in Heaven!
For my other basses, I'm still experimenting. I'm only trying Stainless Steel because I'm sick of nickel turning my hands black. I've decided to basically try them all in order to find the perfect SS strings for each respective bass.
Currently have Apex Traditional Cryos Stainless Steel on my Stingray5. So far, they sound fantastic! Seriously, I've never had so many compliments on my bass tone.
Currently have Roto66 Stainless Steel on my Ultra Jazz. I haven't gigged it yet with these strings, so no opinion yet. I have a feeling I'm going to like them. I had Apex Traditional Cryos SS on it before, and I liked the sound of those, so we'll see how the Roto's do by comparison (and if they last as long as the Apex).
Currently have DR Hi-Beams on my Peavey Sarzo. They sound ok on this bass, but I'll be trying others.
My MIM Jazz (that has never been gigged) currently has DR Pure Blues. They'll be coming off because (as stated above) I'm tired of nickel turning my fingers black. They sound ok, but I think I'll put Roto66 SS next.