The PM8005 for sure. No contest. There is more to good music reproduction than just watts. The refinement come from the stereo pre-amp and sorry to say, the 2 channel pre-amp sections, even in pure direct modes, on most AVR's are an afterthought.
Also, the PM8005 is built at Marantz' reference factory in Japan, is heavier, has a toroidal transformer, much better discreet parts and is 4 Ohm rated. The MM7025 is none of the above. Also, despite the wpc rating into 8 ohms on the MM7025, I would bet the PM8005 actually is the more powerful amp. Certainly the better sounding and will match up well with your MA's.
Mating a quality stereo integrated amp w HT bypass into a HT setup is a smart and great way to get a quality 2 channel system for music. The best of both worlds. If you just add a power amp to your AVR, you still only have a HT system. This is the exact way my system is configured as I have the PM8005's big brother - the PM15S2 LE. It replaced a Parasound power amp of far greater wattage and I couldn't be happier - it has taken my 4 Ohm Vienna Acoustic speakers and music listening to new heights.
Hope this helps.