Thanks for the kind suggestions. As you can gather from this topic I have decided to buy the Montblanc Nicolas Rieussec Rising Hours in Gold. In my previous shortlist there was also the opentime with black dial and the opentime with white dial. I decided to buy the rising hours because in my view it justify the price difference for a very unique complication. With other very nice (and still very much loved) watched in my collection I am trying to limit new purchases to something that is both lovely and distinctive. I also very much like the day-date available on the rising hours but missing in the other models.
The watch is fairly big and as you can see I don't have a big wrist but I do think that it still fits pretty well:
Closer View:
The open back of the watch reveals the wonderful manufacture movement MB R 220 and the gold rotor.
Here with another excellent product from Montblanc, a bag, as a background:
To be sure that the watch was not too heavy or uncomfortable for my wrist I went with my Patek Philippe Nautilus that is very light and thin - it looks interesting near the Montblanc logo 
After spending almost an hour trying the watch and double checking if it was comfortable enough I decided to take it home. The Montblanc watch box is also high quality - I suspect that this is used for all the
Rieussec watches (steel or gold) but I am not entirely sure if there is a difference in the boxes/presentation
The watch comes with the 500 hours quality certificate which I think is a great tool to increase the brand image and guarantee that the production is of the highest quality
Other Rieussec including the anniversary one (that is manual winding and more expensive) were are also available in the boutique
And now going home the Rieussec
As you certainly know the purchase of a watch is very much linked with emotions so it is difficult to review a new love
this said I can comment on some aspects of the watch and why I decided to buy it: - I love the unique design and the rising hour complication that is not available in other watches and has been patented by Montblanc. To me this is a sign of true innovation and a distinctive element of Montblanc
- It is one of the few chronographs I like with the monopusher function and the location of the button
- I think that it looks impressive yet traditional in a way.
- The personnel at the boutique was very kind and allowed me to try pretty much every model and take my time in the decision without any pressure
Things to consider:
- The watch is fairly thick so it is probably not for everyone. In terms of size it is also not too small but thanks to the lugs design seems pretty wearable also for smaller wrists like mine.
- There is no lume so it cannot be read at night (which is fine by me as I have other watches for that!)
- Availability is mostly through Montblanc boutiques
I am a bit fan of Montblanc writing instrument and leather products and I am very happy to have now bought the most unique in terms of complications and look (and expensive!) watch in my collection.
Christian