DAC VS AVR

Greetings,

I'm having a problem.  I am very close to having my ideal setup but am having second thoughts about direction.  I've been building my home theater based on only using two channels.  So I started with a pair of Zu Omen Def being fed by a Marantz PM6005 with built in DAC being fed by the optical out of my Samsung plasma tv.  I'm living in a house where surround sound is not in the cards.  So I figured to just have an amazing two channel system and use it for 75% movies and the other 25% for music(vinyl and spotify). 

So going along with that I wanted to replace the Marantz with a Vinnie Rossi LIO.  A modular integrated amp with some great modules like a mosfet amp for my very effecient Omen Defs and a pretty darn good DAC.  I figured such a nice piece of equipment would outshine my entry level Marantz. 

So right now my Marantz is in the shop for repair.  Most likely a cheap potientiometer is broken.  So until that's fixed I'm borrowing a Marantz slim avr.  So now all my sources are going to the avr and one hdmi to the tv.  Now the avr is doing all the decoding and i'm liking what i'm hearing.   My question is this:  Is the AVR doing a better job of decoding and down mixing into two channels than the Marantz built-in DAC section? 

I'm looking for the best of both worlds I guess.  I want something that is strong with movie soundtracks and good with 2 channel music.  But I also want something that costs as much as my speakers.  So I'm stuck between a Vinnie Rossi LIO and a Marantz AV8802A.

Pardon my typos and tangents,
-Patrick