How are MTX 6000 series subs?

I'm about to buy 3 mtx 6000 series subs 10" from this guy. I want to know if they are good or not. I'm probably going to be selling them to a friend (hehe profit!) and i was wondering if they would be good subs for a truck? He wants to put 2 of them in some boxes that fit behind his seats. His truck is like a 95 chevy cheyenne. I MIGHT keep them for myself and put them in my hatch in a sealed enclosure. If i keep them i'll have 3 of them in one sealed enclosure.....would it sound pretty good? i'm a COMPLETE newb to this stuff so PLEASE tell me!!
 
Very good. I had a 12" that lasted through pounding b4 blowing 3 years later because I was testing it for a competition the next day. Got another one and it's about 8 months old. Very hard hitting subs.