I've stayed their every week for the last couple of months and would add a few comments.

Upgrades are hard to come by. As a Plat, I think I've had one, and that was after I made a fuss because my colleague (who had no status at all) was upgraded to the exec floor while I was offered zilch.

The rooms are larger than most Marriott rooms in Europe, but a little dark & there are limited power sockets. (I've had to crawl under the desk and unplug various lamps)

Only access to the exec floor is via the lift which can take forever. The stairwell doors to the 7th floor are locked from the inside so you can't sneak up that way. I raised this with the staff as a potential issue in case of a fire (If you were on the stairwell with fire below you), but got no response.

Evening snacks in the lounge are good, as is the restaurant.

All in all not a bad hotel.