I wouldn't return to Albergo Diffuso Mannois. I booked a suite with a jetted tub, but after making so many hotel bookings for this trip, I forgot I had sprung for a nicer room. I only realized now writing this review that I did not get what I paid for. The room, while sort of a suite, definitely had no tub, jetted or otherwise.
The room was two floors -- ground and basement. Main bed and a couch on the ground floor, a second bed and the bathroom in the basement. The bathroom was freezing. If we turned on the heat, the ground floor became unbearably hot (i.e., heat rises). To make matters worse, no hot water in the evenings. Just warmer than lukewarm. Mostly had hot water in the mornings, except for our last morning. The shower was really nice, though, when the water was hot.
The bed was incredibly firm, and the pillows were, too. The linens felt cheap and scratchy. Sleeping was not comfortable, in other words. Also, I noticed a couple of spots of blood on the bed in the basement. I didn't say anything to the staff because we weren't sleeping in it, and figured they'd notice and change it. But they didn't, even with daily cleanings.
Finally, on our way out to dinner one night, our gate key broke in the lock. Almost trapped ourselves (and other guests) inside the courtyard, but thankfully reception staff hadn't left yet. They left daily ~8pm, so not sure what would have happened if they weren't still there.