I've mostly had 45–105 GHS Boomers on my 424. I always play with both pickups on, and they fill in the gaps in the sound very nicely. The stiffness and tension suits me.
Now I've got a P as well, I would happily trade a little of the Boomers' presence for even more warmth in the mids, to increase the contrast between my two basses a little.
Option (1) Fender 7150. I've the Fender nickel-on-steel 7250 on my P, and like their tension/stiffness/feel/price, so these all-nickel hexcore rounds would be an easy choice.
Option (2) DR Nickel Lo-Riders. Said to have lots of warmth for NPS hexcore rounds, but they are a lot more expensive, and might be lower tension than I like.
Has anyone tried either the 7150s or the Nickel Lo-Riders on their BB?