KR, with my time pishing around with them, the most noticable differences were produced by changing pups. I wouldnt have bothered with a Bart in the Bobanez, and the Schaller was just right for it.
A Bart in a US P however is something very special if you like that deep solid thump that a P produces.
Where I not a 'dyed in the wool' completely blinded PRS person then, thats what I'd have - 1 fretted and 1 fretless US P bass both with Bart 8S pickups.
Bet you're regretting letting the Bobanez go now arent you!