After 18 years on 4, I went to 5 in 2000. If you make it the "only bass you play" for a few months, you'll be there. Switching between the two (esp on the gig) takes more time tho!
One of the troubles with most 5s is that it's hard to get a good, defined sound for low notes on the B string AND get a decent sound up the neck. (if B sounds good, higher notes are thin, or higher notes good, B booms...) So I ended up not using the low B so much UNTIL I found a SR5 (just a few months ago...)
To me this is the thing that makes the SR5 incredible. Full, bassy, ringing up the neck, and defined and growling low D, C, B ... at the same time. Now I'm playing lots more grooves down between low D, C etc. !
btw..my first 5 was a Peavey Cirrus 5. Great bass. But the SR5 sound totally wins, for me.