Why would deciding what sub/s to buy hold you back from ordering the A/V1's?
I don't get it. If anything having the A/V1's would mean you'd be able to test out some subs to see how they work with the A/V's, but really any good to great subs should 'match' these speakers.
Also, if you're building 7 A/V 1's as kits I'd think you'd want to get working on that which would give you some time before they're complete and ready to be matched to any subs. And then guessing Danny will have all the info on his new drivers and cabinet designs by then.
In the end if the GR sub/s don't look like what you exactly want... just get diff. subs for your A/V1's you said you're wanting to buy.