Not in decades, but why Denon?
I would and have bought an OPPO BDP-83 for $499.00.

Charlie:

Denon is still an excellent machine in any book. BUT, that said give the Oppos a look. What sopecifically are you after in a deck.

But were in the market right now, I would be looking at Oppo. Even at that something to give some consideration to if you are looking now, and don't poo-poo it, is the new 3D standard, and yes i do have thoughts in that area. it's getting to become a very complex market.

A screen so you are using a projector. That will actually be a plus in 3D

Projector's have their pros and cons particularly with today's LED flat panels. The LEDs will deliver a sharper and crisper picture with far better contrast ratios. BUT they are limited in size unless you have BIG money and I would give the edge to Projectors for 3D work. The flat panels use a technology refered to as Active Shutter in the glasses, the glasses interact with the screen via wireless link and the Active Shutter has the lenses turning on and off at a very fast rate, alternating left right left, etc. faster than you can see it but it's there nonetheless. This technology is not cheap, I think the glasses are about $150 per pair. The projector's from a 3D viewpoint will be able to use glasses very similar to what is used theatrically...much cheaper. I don't know how soon we are going to begin seeing 3D projectors, but it is worth your thinking about it

A comparative test in the German Video HomeVision magazine gave the edge to Panasonic's plasma-based 3D solution over Samsung's and Sony's LED-LCD 3D screens.

Personally, however, if I were buying now, 3D would not be my primary concern.

Returning to the OP's questions: I have had plenty of good experience with Denon equipment. Always excellent build quality (their better models are really built like a tank), and its machines have always been very reliable for me.
That said, the Oppo BDP-83 is definitely a serious contender. I bought a region-modded 83 last year and have been very happy with it. What gives it the edge over a Denon machine is its lightning speed as well as some fairly unique features such as subtitle shift (useful for non-anamorphic DVDs). Also, Denons are more sensitive to disc faults than the Oppo.

EDIT: is the Marantz receiver you have up-to-date? Can it decode all Hi-Def audio formats as well as DSD (SACD)? In that case going for the standard Oppo would be a no-brainer and also give you SACD and DVD-Audio playback - you could spend some of the money you saved on getting some SACD and DVD-A discs to enjoy high-quality music.

Quoting Ace_of_Sevens:

Quote:
Are there even any projectors on the market yet that do 3D?

Ummm Ace, I think if you re-read my post you might be able to figure out that I answered yiour question BEFORE you asked it. Which leaves me wonderiing WHY you asked.

Quoting Prof. Kingsfield:

Quote:
Quoting Ace_of_Sevens:

Quote:
Are there even any projectors on the market yet that do 3D?

Ummm Ace, I think if you re-read my post you might be able to figure out that I answered yiour question BEFORE you asked it. Which leaves me wonderiing WHY you asked.

I ask because you could also use active shutter for a projector. You need a specialized screen to do polarized and I'm betting it costs more for the projector as well.

I worked at an electronic Retailer until just recently and all Denon Products we had in the Hi-Fi Dept, be it Receiver, CD Player or BD Player the were all top notch.. Also not even once was one of those items returned by a customer... That said, one usually can't go wrong with Denon.. (Or Onkyo but they have yet to release a really good BD Player)