What is a good Sub for my xterra.?

I want to put a sub in the back of my xterra for my birthday. I need to know a few good ones that I can get, along with an amp for around or under $300. The one im looking at the most is an MTX terminator





* 2 12" Terminator Series Subwoofers Included


* Power Handling:


o Peak: 1200 watts per pair / 600 watts each sub


o RMS: 400 watts per pair / 200 watts each sub


* 2" Aluminum single 4 ohms voice coil


* Rubber Surround


* Polypropylene Cone


* MTX Audio Logo on Dustcap


* 48oz. Magnet


* Frequency response: 37-150 Hz


* 1-year Sonic Electronix warranty (on subwoofers only)








along with the terminator amp


* Terminator Series Class D Monoblock Car Amplifier


* RMS Power Rating:


o 2 ohms: 200 watts x 1 chan.


* Max power output: 400 watts x 1 chan.


* LED power and protection indicators


* Selectable bass boost (0, 6, 12 dB at 40 Hz)


* Mono gain control


* Smart engage auto turn-on circuitry


* Built-in adaptive cooling fans


* Fixed low-pass filter (85 Hz, 18 dB/octave)


* CEA-2006 compliant amplifier


* Frequency response: 20-85 Hz


* Dimensions: 13-1/16"L x 10-3/16"W x 2-1/4"H


* 4-gauge power and ground leads recommended. Contact us for information regarding a discount on a select amplifier kit when purchased together.


* 1-year Sonic Electronix warranty (on amplifier)











I want to know if that is a good combo or what i should change about it. I want to get the best sound i can without blowing anything by making a bad decision. thanks.|||pick up a re audio xxx from ebay or craigslist, best loudest subs out there i picked mine up for 350 used and its unbelievable, only if you have proper electrical upgrades and wiring (and an amp that will give it enough juice!)|||sorry but an xterra is not a car to be bumping in. you're better off moutain climbing or something