Audio Systems: Amp size?, rockford fosgate, two subs


Question
QUESTION: I was looking at buying either two MTX T9512-44 (12" 2000W Dual 4-Ohm Subwoofers) or two Rockford Fosgate T212D4 (12" 2000W Dual 4-Ohm Subwoofers).. First which would you recommend.. I am getting a Q-logic vented box either way.. I listen to EVERYTHING... Also with either which size amp do you recommend? And it will only be power the two subs so would I need a 2-channel?
ANSWER: well.  these are both quite high end subs. right off the bat I see the MTX is only about $350 per sub and the fosgate is like $700 per sub!  so the fact that the fosgate's are twice the money probably means they are higher quality.  they're both big name subs so I doubt that there's a difference in "paying for the name" if you know what I mean.  
they do have some similar specs.  they both have 4" formers/voice coils which is nuts for a 12" sub, they both have very large magnets, 260 oz for the mtx and like 305 for the fosgate.  this means they are definitely going to have a very high output in a ported box at the port frequency. so if you want these subs to be musical definitely tune your box low.  they will put out plenty of 40hz all on their own without the help of the port so shoot for 30hz or even 28 for the port frequency to get a flatter, fuller, deeper sound out of them.  I have a MONSTER sub with a 360 oz magnet on it and its SO loud at the port tune frequency that I actually have to EQ it down 5 db!!!
If you're not sure at all what I'm talking about with port frequency and all I can explain, its pretty involved to do it right so you may want to get a custom made box done for you at a local car audio shop.  These subs will need VERY beefy, well braced boxes so I definitely wouldn't get an off the shelf box like a Q-logic,  you'll either have to make it yourself or get it custom made for you for it to sound right. THE BOX IS EVERYTHING!!

No you wouldn't use a 2 channel amp especially for subs this beefy.  you would use a mono amp.
if you want me to pick an amp for you, tell me which subs you decide on and if you have a brand preference and tell me your budget for the amp please.
look forward to hearing from you.

---------- FOLLOW-UP ----------

QUESTION: I decided on the MTX T9512-44 (12" 2000W Dual 4-Ohm Subwoofers)... I think that they would fit my car better.. Thanks for the box suggestion; I was thinking the same thing but doubting myself... I wanna hook an individual amp up to each sub... I really prefer Kenwood amps but willing to change brands if you can suggest a better one..

Answer
if you like kenwood go with them if they have an amp that is a good match for these subs.  personally I recommend allot of poweracoustik amps just because they are a good bang for the buck but in your case I don't think I would go with them.  these are pretty beefy subs and you are investing allot of money so go with a more name brand amp.  I've had allot of good success with fosgate amps before I found the poweracoustik stuff to be 1/4 the price and about 80% as good.
As for the box, please consider it to be the most important part of your setup.  I know that sounds silly cuz it's probably the cheapest part and doesn't seem to be as important as the equipment itself but the box determines how the sub sounds so its EXTREMELY important.  the same sub will sound completely different in different boxes. and for the girth of these subs it will have to be built quite tough.
Good luck!