It really depends upon one's style of playing, the types of music one plays, etc.
I use - and love - FatBeams on all my fretless basses. And the set of Hi-Beams I have on my Carvin SB5000 is working out just fine. But I play all those instruments strictly fingerstyle. And I don't really play rock on any of them.
For rock, I still prefer a good set of hex-core stainless steel strings, set up with low playing action. If necessary, I'll go to a lighter gauge set than usual. And while I still play mostly fingerstyle, I reserve the option of playing with a pick.
Either way, the hex-core construction allows me to hit a bit harder than I would otherwise. The hex-cores interact with the frets more musically - because they're set a bit lower. They therefore tend to generate a bit more harmonically rich overtones.
Stainless steel Lo-Riders do the trick for modern rock, IMO. But as usual, different tools are optimized for different tasks...
MM