wilson puppy with martin logan descent??

I have not heard this combo. But, I have heard several speaker sub combo's that don't integrate real well. Your WP's are a very revealing speaker, I have wp 6's. If you feel you are missing bass...are they positioned right? Right amp and cabling? Right front end? If so and you still want more, I'd only consider Wilsons current powered sub, it's likely the only thing that will match with your current wp's.

Any thing else, will be be missing proper integration...

IMO...

I agree with Jfrech--I don't believe the ML is in the same league as the WPs. Perhaps a really good REL might work, but to be safest use a Wilson Watchdog or WHOW, if you really need that last half octave of bass.