I just thought the neck H sounded really awesome, especially with the ability to put it in series or parallel. On the HSS models (and SSS for that matter), the neck single coil makes sounds like no other Musicman before it. Its a really cool tone, but may not be great for everybody. And for some of the slappers out there, they may find the HH easier to manage.
All that being said, there is hardly a bad tone to be found in these basses and the traditional MM bridge humbucker tone is on display in maybe its finest form.