Oaudio TC2+ 15": Worthy North Creek Thunder Replacement? And cabinet questions

[AhmedF]

I have an opportunity to pick up a raw, unused 15" O-Audio subwoofer (a) from my cousin. It is a really nice looking subwoofer, with a beefy frame and an imposing black saucer cone. It would replace my current subwoofer, which is a North Creek Music Systems Thunder (b), which uses the Peerless XLS12 woofer and passive radiator. I love this subwoofer. It is taught, punchy, precise, and defined. It got even more precise when the North Creek plate amp died, because I replaced the amp with a Velodyne SMS-1 equalizer (c) and an Outlaw Audio 2200 amp. The problem is that I moved recently, and this sub runs out of gas in my new greatroom. It can no longer keep up with my speakers, which are NHT VT4 towers powered by an NAD C370 amp, the way it did in my old smaller living room. I have searched this forum and found high praise for both drivers, though many more people seem to have used the Peerless woofer. Before I bite, I have a few questions.

1) Will this driver satisfy me? I mean, after I set the EQ on the SMS-1 manually will this O-Audio woofer sound similar to my current subwoofer, except with one more gear, or will it sound much different? Will it integrate well with my speakers?

2) What's the smallest box I can use with this driver? I know it won't be as small as my current subwoofer, because the driver is bigger, but I don't want a huge eyesore, either. I assume I want a passive radiator, because that's what my current sub uses, but I've also heard that sealed subs are even tighter sounding. I played with the program my brother recommended to me, a free Excel plugin called Unibox (E), and I didn't really understand how to model passive radiators. He told me that he didn't know where to buy huge passive radiators, either, and that I should play with ported boxes in the software. Any thoughts?

3) Can I still use my current equalizer and amp with this woofer?

Thanks,

FA

Links:
(a) O-Audio TC2+: http://www.oaudio.com/TC2_PLUS.html
(b) North Creek Thunder subwoofer: http://www.northcreekmusic.com/Thunder/ThunderInfo.htm
(c) Velodyne SMS-1: http://www.velodyne.com/velodyne/pro...p;sid=676i995q
(d) Outlaw Audio 2200 M-block amp: http://www.outlawaudio.com/products/2200.html
(e) Unibox Excel plugin: http://home20.inet.tele.dk/kou/ubmodel.html