Can you tell about what volume your boxes have?
That JBL does have 6db xovers.

MFK, either of those subs will produce very good bass. I've owned both and as long as you follow simple rules; put them in proper boxes (sealed or ported really doesn't matter for SQ as long as they're correct for the sub(s)), power them sufficiently to get to the volume levels you want or that they can handle, and match them with the rest of your system (x-over point, eq'ed, level matched), and they'll sound great. The main difference between the two is power handling, the R's will get a little louder and stay in better control at high output. The Perfects get more than loud enough for daily driving/listening and sound terrific with all types of music, and I listen to everything from opera to metal.

@ AAAAAAAA, Well for this system, the box I picked up, I didn't care about the volume, I cared that it should fit. It was for 55 bucks and I didn't bother measuring the volume.
I'll get back to you on that!

@ veeman, thanks alot man. I asked about those because some people I know are letting them go at decent prices. And I have to pick one! I think the perfects should do it for me, but I'm still considering what other people have suggested, like the JLs and the IDmaxs.

Anyways, any word on the MTX components?? TX6001, do they sound good?

It's quite clear from all the responses you got, that subs are not that critical for SQ. In my experience install and tuning is most important, then front speakers, and then a head unit. Of course, you can not do much tuning if you have no good sound processor(head unit). Subs and amps should mostly only fit your application instead of dwelling on their SQ, unless you become a perfectionist like many on this forum. All in good time, buddy:) So spend most money on the front speakers.