1 night at the Nice Boscolo, 1 night at the Monaco Marriott, 3 nights at the JW in Cannes and 2 nights back in Boscolo. I did consider Le Meredien (SPG) but so far my experience with SPG has been spotty and I did not like the reviews.
All were booked on points. Monaco and Boscolo contacted me about a week in advance and offered help, directions, asked if there were special requests. JW in Cannes sent a canned greetings email with no personal contact.
The best upgrade was in Monaco: a two room suite with a balcony. JW in Cannes offered a smaller room but with the view of Le Croisette and the sea. Boscolo upgrade was better for the one night arrival stay then for the two night stay before final departure.
All hotels offered Plat breakfast. JW and Monaco was a standard Marriott English breakfast buffet and an omelette station. Boscolo offered a very basic cold cut and continental buffet plus a limited selection menu. But Boscolo made the best espresso!
All offered arrival gift choice. Monaco went beyond the offered selection. Boscolo also gave us a bottle of sparkling wine for our anniversary.
Hertz Presidential Circle (available to Plat Premier) offered to upgrade the booked compact stick-shift to a convertible Mini Cooper for just extra 6-7 euros per day. Initially they upgraded the compact to a diesel SUV, but I went back to renegotiate...
Delta crossover rewards upgraded to first class on both US legs, but no upgrade on the transatlantic leg. I did purchased a Delta Comfort seat upgrade for $124 and it was definitely worth it.