Samzx12...
I prefer the Pioneers over the Marantz for a number of reasons, first and foremost that to my ears the separation seems better. Also, they're easier to maintain - labor on Marantz adds up quickly according to two separate techs I've had check things out.
Secondly the Pioneers strike me as more "realistic" in their sonics; my experience with McIntosh solid state and tube amps is similar. I recently purchased the new MAC6700 solid state receiver and grew to dislike its tubelike voicing; I traded it back for the new Mc275 MKVI. If I want tube sound I might as well use a tube amp, right?
These receivers still sound great, no matter who may have thought of them as "mid-fi" then or now. They still LOOK great, too. Admittedly people dig the Marantz tuner dial more than they do the Pioneers', but that's what I dig about both - they still make people gawk and ask questions.
A couple of years ago my girlfriend's daughter was getting her pre-ceremony wedding pictures taken in her living room.
When the photographer and his two assistants saw the Marantz they begged to hear it. After obliging them they even offered to buy it for a pretty handsome sum. Of course we refused the offer.