$2700 for the combo is kind of steep, but I guess it depends if you want brand-new or not. Accessories4less.com has two refurbished AV7005's, one for $999 and one for $1099. A while back they had the MM7055 amplifier for $799 refurbished, which I bought. Brand new the MM7055 is $1200, so that plus a refurb AV7005 would cost you ~ 2200-2300.
Alternatively, depending on how you feel about ID brands, an Emotiva XPA-5 would be $899.
I run the same Marantz Preamp and amp you are considering on less efficient speakers, and the combo works great.