I've only compared the Custom Custom directly with the JB. The Custom Custom with 500K pots would have less treble and less bass and alot more mids than the JB with 500K pots....although the CC with 500K pots is brighter than the JB with 250K pots.
The Custom 5 would probably have more genuine treble or upper harmonics, IMO, than the JB and less mids.
Lew