Last year around this time i bought a Franx99 setup from mtx thunderform.

It in, are two 10" thunder 4500's and an integraded amp.

(here is the link) http://www.mtx.com/caraudio/products/manualsQuickInstall/thunderforms/FRANX99_specs.pdf

the link basicly just says

Dimensions: 83⁄8"H x 515⁄16"W x 12"D
Weight: 30.3 lbs
Power Handling: 450 Watts RMS
Subwoofer: Two 10" Thunder4500
Amplifi er: 200 Watt Class D
(on amplifi ed models only)
Enclosure Volume: .92 cubic foot, sealed
Impedance: 4 Ohm
(on un-amplifi ed models only)

now. i just bought a Poineer GM-D7400M Amp ... which specs say.

200W RMS x 1 (4 ohm) 20hz to 240hz < 1%THD+N
400W RMS x 1 (2 ohm) 50hz < 1% THD+N

and after doing some searching via google, im even more confused if this is going to improve my performance on the subs, or keep them underpowered, or maybe blow them?

The person at the retailer that sold it to me said it will improve them by almost double. But, like i said after researching, im looking for a second opinion.

If this will work, how should i hook it up? 2ohm, or 4ohm? And how does each effect performance?

Any input is greatly appreciated.