Yeah, that will be going up, for the US soon, i've seen the 2012 pricing already, Canada it's a $480 amp, MSRP.

Your question is one that has been asked a thousand times, with a thousand different answers.
Obviously, recommendations can be made as far as power output is concerned to match your speakers power handling capabilities, but there are so many other factors to consider as well.
Everyone has a favorite brand, and model, and will give them high regard to anyone who will listen. Your best bet is to do your own research, consider all of the factors involved (class a/b, d, ect power output, S/N ratio, Thd, ohm stability, size, appearance, the list goes on and on) and chose your weapon.
There are many places you can find out there that are very informative, and can guide you on the right road.

Good luck in your search.

I have a nismo with just front speakers. I am adding rears and sub.

Well that's precisely the question, what power ratings should I get over 4 channels in 4ohms to match the power of the speakers and subwoofer? Keep in kind I would probably bridge 2 channels for the sub. I know I want less than 1% total distortion and would probaby go with a class d because they are usually smaller. I could not care less about brands, jl, alpine, RF, Kenwood, ba etc they are all great.

The mm's would just give you a smoother tweeter and better bass response with the bigger woofers.

That amp should work fine with them. Just make sure no matter what you get you adjust the gains. It is all under the audio 101 section.

I have two of the Alpine PDX amps one under each seat. They are nice amps and fit easily under there.