Well are you goin to have dual chambers or just one common chamber? Divider in the middle so each sub has its own box?
definitely want a dual chamber. I know "in theory" your subs should be matched perfectly, but they are not. put em both in the same box if you have to, but make sure you have a solid divider in there (don't use anything thinner than 5/8" mdf) you don't want rampant waves bouncing around and cancelling eachother out. we can't have that, now, can we?
You mean one or two ports in each enclosure? if so, that all depends on what you plan on tuning the box at. I have two 5 1/2" x 11" in each side of mine, but I have 9.5 cubes for each sub and tuned them to 18hz for two 10's, you should be able to get away with just one large port, but if you prefer the looks of the dual ports, you can use two smaller ports. (for each sub).
actually I think that sealed boxes are better for rock. I like bandpass for all around sound (not particularly strong anywhere except deep notes), and my ported box sounds great with all my music, but it's got plenty of power. I guess you listen to mainly hip hop? ported boxes are fine. You just can't get away with overpowering a sub in a ported box. It allows the subs to over extend (if you put too much power to them), and you can damage the subs. By the same token, you can hurt them by using too large of a port, thus not giving the sub the resistance it needs to stay intact. whatever you use, make sure you get close to the sub's recomended volume, or build it yourself so you know it's right!
