I can't speak for those specific hotels, but I can say that I have stayed at several Comfort Inns before, and they aren't bad. The rooms are average, but nice. Sheraton is another nice hotel brand, and both of these hotels must meet certain standards by their franchise owners (Choice Hotels for Comfort Inn, and I assume Sheraton for the Sheraton) in order to keep the Comfort Inn and Sheraton names.
These hotels I think will be fine, just going by the brand names. I know for sure Comfort Inn offers a continental breakfast (whether you look at it as free, or included in the price of the room is up to you). I'm not sure about Sheraton.
2007 - Majesty of the Seas
2009 - Enchantment of the Seas
2010 - Freedom of the Seas