I also witnessed the weakness of their "B" a few times. Simply sounds wrong, at least compared to a USA Spector or a USA Lakland active 5 string jazz bass.Please, go find one and try it first. I've had Fender 5 Pro (and Ultra) before and sold them quickly. Now in fairness, the bottom 4 strings are great and they would be a nice addition to your collection, but their "B" won't come anywhere close to a Stingray "B". Its pathetic. Sure with enough knobs, switches and sims you can make it sound good. But really..... is all that necessary when your Stingray already does that. I don't know that you need 2 of them..... but that's another story.
And don’t get me wrong, I’m a big fan of Fender p and j basses and I play their 4 strings on a regular basis.