Atmos + Ext Amp

[ArieS]

So right now I have the Pioneer Andrew Jones Atmos speakers that I had bought with a Pioneer SC-87. I returned the receiver when I found out that it couldn't do 7.1.4.
I'm now left with the Atmos speakers but no receiver to use them

So I've decided to get the Pioneer SC-95 as it can do 7.1.4 with an external amp.

My dilemma is, should I get an ext amp for the back surrounds like this one:

http://www.amazon.com/Onkyo-M-5010-2...ereo+amplifier

The wattage on this one seems only enough for the Surrounds, right?

Or should I get something better and use the ext amp for my fronts?
Maybe a 3 channels amp, if such a thing exists? I live in a townhome with 1 common wall so I don't blast the sound when watching movies.
So would an amp for the front 3 be worth it?

My only limitation is that my AV rack is pretty full so I can only get an ext amp not taller than 6 inches.

What do ya all think?