I am a bit of a Dennison devotee, in fact I am wearing an 18K pie pan Dennison Deluxe on my wrist right now. You might find our very own Andrew Romains essay on Dennison useful
http://omega-constellation-collecto...01/from-advent-of-bretton-woods-monetary.html
As others have said they are great and very well made cases, Dennison had a very close relationship (including some real conflicts of interest) from the early part of the 20th century until their demise in the late 1960's. I too am watching this watch, partially because its in exemplary condition and partly because its 18K and only about 10% of Dennisons production was 18K watches, most were 9K
It looks like an excellent example and what I would say is that he quality of Dennison cases is outstanding, although their 'current' designs were mostly based on slightly older Omega designs (at the time of manufacture) the quality of the cases was amazing, most likely (as Andrew eludes to in his Essay) because they were pretty much hand made.
Although as Padders has eluded to there is an issue regarding the model number, Andrew has quite an extensive archive of Dennison numbers and as you will see from reading his essay there is a logical process in terms of how they were categorised and numbered.
There are a number of camps on Dennison watches but no one can question that the quality of the 9K and 18K models was second to non and you have the benefit of knowing that they had exemplary swiss made movements with (in many cases) hand made English craftsmanship in regards to the cases.
There are my two Dennison Constellation 18K Deluxe's
View attachment 309229
View attachment 309230
Click to expand...