We spent a week at the Grand Hotel Terme di Sirmione in mid-September 2024. The hotel is excellent, and all the staff are always helpful. The thermal pool was a big hit, you can spend many happy hours in it even when it is raining. The sulphur smell from the thermal pool can at times intrude into small parts of the hotel (the smell is not really noticeable in the open air at the pool), but that is a very small price for such a wonderful facility.
The buffet breakfast is OK but if, like me, you like your bacon thickly cut they will slice and cook it specially on order, along with freshly cooked accompaniments like grilled mushrooms, grilled tomatoes and fried egg.
If you are a dog lover you will not be bothered by the fact that at weekends Italian guests bring their dogs and these are allowed into the restaurant! This is the only aspect of the hotel I would want to change, but having said that we will happily stay there again in the future.