What would be considered an optimal woofer for a passive cardioid enclosure between a subwoofer and midrange?

Hi all.

Originally I was looking to build a double 12" sealed woofer enclosure to go between my BMS 18n862 sealed subwoofers and, perhaps, multiple types of midrange and tweeter combos in a separate enclosure. But I got interested in passive cardioid enclosures after looking through several threads.

In my use case the requirement is 100hz to 300hz/500hz, but the wish is 80hz for low end extension. The specific dispersion goal I'm not fully sure about yet.

The options for woofers I shortlisted for the sealed version was: SB Acoustics SB34NRXL75-8 and Oberton 12NSW600, but after reading about the The Bitches Brew Open Baffle Live Edge Speakers by Perry Marshall I started to wonder if perhaps woofers optimized for open baffle use would make more sense in this case.


For the sake of a more general discussion though my question boils down this:
What would be considered an optimal woofer for a passive cardioid enclosure between a subwoofer and midrange?