I do not think the top will affect much on the sound. I liked this pickup configuration because of the distance from the classic jazzbass: the instrument is silent, very well balanced across all frequencies and with a perfect setup without major interventions.
Honestly I'am not good at slap. I play primarily with the fingers and the pick and Bartolini's pickup do their job very very well.
It has a perfect neck and this is the real reason why I bought this bass