MTX is a very reliable company. The MTX RT1240 is not one of their better woofers though. They are no longer made, and lack in SPL, I wouldnt buy one...
Good deal? Yes. Worth the money/time? No, IMO. I would get a pair of 7500's or something along those lines. The RT1240's are just not very good SPL woofers. I would take two good subs, or even a single good sub, over three low end any day.
mtx is a good company i've been dealing with them for years (i collect mtx subs n amps) i had 4 12 road thunders in a blazer and it was real loud ( 4 12s has to be loud), pretty decent sound quality, didn't pull numbers good tho, only hit 139