I dabbled in 5s a few years ago (Fender mex V, Sandberg PM5, USA Musicman Sub5), and enjoyed them greatly, necessary for the band I was in at the time. The USA MM Sub had the best B string of the 3 I went through.
When I got one first, I only thought about the B string in terms of below the 5th fret, but the more I played, I started using the B string all the way up the neck, was a bit of an eye opener.
Still though whenever I picked up a 4 string, it just felt like home and I ended up shifting all the 5s and using an octaver for low notes.
Not quite the same, but in a live situation I find it's enough for me! YMMV!