Manual vs Automatic, (3520D vs 5120) Long-term Storage, Little Use

I'm currently considering my first Patek purchase for an occasional use dress watch. I like the clean minimalist styles of the 3520D and 5120. I believe the simpler the design, the less the watch will "age" per se. I suppose the whole "give the watch to your grandson" campaign has finally gotten to me.

I'm looking for something I can wear once a week. For the most part, it will sit in a watch case playing second fiddle to an Ulysse Nardin Maxi Marine Diver.

My questions are:
1. For this type of usage, which movement will require the least amount of maintenance? Will I still be required to follow the 3-5 year checkup schedule?

2. If I went with the 5120 automatic, would keeping it on the winder lower the overall required maintenance or should it be kept in the drawer?

3. If I chose the 3520D manual wind, would keeping it on the winder help keep the lubrication fresh and overall lower the required maintenance or should it be kept in the drawer?

I'm relatively new to mechanical watches in general and would truly appreciate any insight given. I also am open to looking at other watches if you feel I may be overlooking something.

Thank you for any assistance you may provide.