ATI 2007 or ATI 1807


I am contemplating on one of the above. I have a small listening HT room
10ft x 10ft and I am presently using a Yamaha AVR RXA-3010 in a 9.2 set up.
I am planning to hold on to the Yamaha for now and use it as a pre-amp and buy a ATI 1807 or a 2007 for better dynamics and so on..
It their a huge improvement in sound quality with the ATI 2007 to justify the extra cost over the 1807?
I would be most grateful for any advice please.
morganmadden
Ok all, thank you for all the advice. I have now purchased the ATI 2007. I am thrilled with it, but really only since I ditched the Yamaha RX-A3010 as a pre-amp and substituted it for the new Yamaha CX-A5000. What a pairing!. I can hear every nuance, such doors closing, sounds in the back-round I did not take notice of before and so on.
The Yamaha CX-A5000 is a huge leap up from the RX-A3010. There are several rave reviews for the 3010 and it is a good receiver, but the CX-A5000 IMHO is streets ahead and everything all the current reviews are saying- great value for $ and probably under priced. Paired with the ATI 2007...
Audio nirvana at last!
Congratulations! I really think ATI should be better known. Excellent amps. Also heard good things about the Yamaha. Enjoy :)
ATI is far superior even today , those can drive any speaker (yes even 0.8ohm dipping kappas) done it ! Measured 11 amps pull no sweat by the ati . 

I used a Crestron cnampx7 which is based of the 1807 with the different that one is 200wpc instead of the 180 of the ati. For the rest precisely the same amp 

These are audiophile graded multi channel amplifiers. Yamaha should not even be mentioned in the same sentence. Especially not of you understand engineering a little bit.