We stayed at the Sheraton - it's an ugly block from the outside but inside it's very pleasant, actually better than it needs to be in this tourist hot-spot. I wouldn't say the views from there are great . . . no better than the Cataratas on the Brazilian side. As far as general sightseeing is concerned, I much prefer the Brazilian side which gives amazing panoramic views whereas the Argentinian side gives more close-up views. But my big tip is this: the weather here is very changeable so allow at least three nights to stand a good chance of getting sunshine and gorgeous skies. Actually, we liked this place so much we could easily do a week.