Wavtech mini series amplifiers are awesome. Clean sound, powerful, and work flawlessly with factory head units (or aftermarket too!) Why spend another $100-150+ on parts to install an amp off your factory radio, when these amps have that built in? No brainer.
The 300.4 boasts plenty of power, with 50 x 4 RMS @ 4 ohms, or 75 x 4 @ 2 ohms.
Bridgeable also, so it can be 150 x 2 RMS, or 50 x 2 & 125 watts RMS