FWIW, I found the IC Prague to be an excellent property. Granted, it's not quite up to the level of the 5-star MO or Four Seasons, but the rooms are spacious, location good, views of the river pretty. If you're trying to save a little money, it's definitely a solid choice.

I stayed one night at the Four Seasons in Prague, so I can't report on much besides the fact that it is a stunning hotel with great character.