Ah cool, the 'beat the W7' game.... again.
What are we wanting to beat W7's at? Output? SQ? SQL?
If its raw SPL, that's easy enough.... build a serious SPL install. Look what Nate Munson did with a single 10... almost 170db. So Im confident you could build something, with just about any good subs, to beat your friend's SPL score. Only question is how serious you are about. If your seriousness only goes so far as to try to find speakers that will magically drop in some prefab sealed enclosure and start owning your local lanes, you aren't serious enough.
If you want to beat a W7 in strict SQ, that's easy enough too. There are many more musical subs on the market than the W7, assuming the proper enclosures.
But, neither raw SPL or strict SQ are the W7's bread n butter. If you are wanting to beat it in SQL, you're gonna have to step up to something like an 06xxx and start using xmax figures to back up your decision, try one of the other 'supersubs' similar in performance to the W7 and rely on 'personal opinion' to decide you own a better SQL setup, or give up and accept the fact that the W7 is still one of the top SQL subs made on the planet, and simply finding another subwoofer that will 'blow it away' in SQL just isn't gonna happen at this point.