As a biased "R" vessel cruiser with Oceania and in the past Regent I found the Marina to be very different in regards to crew, design and passengers.
This was our first cruise on either of the the 1250 passenger O class vessels and our 5th on Oceania.
I approached it with an open mind being there would be more people on board, a more modern vessel and my bias for R class . We had a Cabin on the Concierge Level(deck 9). We embarked in Callao(Port of Lima).
On entry the cabin did not seem to feel that much larger than the one on "R" except for the bathroom.
Storage was useless. There was a lack of drawers. On R vessels for the same length cruise last year around South America had found it easier to store things. Some of the drawers on Marina were very deep but short in length and only came out 2/3 of the way so clothes difficult to put in there. The cupboard for hanging up clothes seemed to be quite small and the doors would open at the slightest movement of the boat and the light would come on. I used a shoe to stop that happening. The area near the sofa and little table was not much bigger than the R class boat. Balcony seemed to be similar in size. Some of the issues mentioned have been raised by previous cruisers
Bed was fine except it did not appear to be a large King bed and it seemed to be a little short in length.
Bathroom was fine apart from shower area(not the one in the bath) was a little small or should I say cosy. However, still managed to use it ok.
Once everything stored the cabin was fine, clean and functional and suited our needs.