Angled sealed box

is there a difference in performance between an angled box, and a square-shaped box?

Will either of these work for the MM2124?

http://sonicelectronix.com/item_2.html

http://sonicelectronix.com/item_7549.html

its recommended to have an internal volume of .88 cubic feet. but both of these are a little less, would it make that much a difference?

I'm gonna buy a 2nd enclosure rather than build one b/c school is starting Monday and i simply wont have time, plus its not like they're expensive either.

Thanks!