If you like fun and funky and want to stay in South Beach, you'll struggle to get a better hotel than the Pelican. The staff are great, it's in the heart of Ocean Drive and the rooms are all pretty cool (both in temperature and style).
We stayed in Power Flower which was remarkably quiet given all the craziness going on outside. But the soundproofing between rooms was very poor, the ceiling fan is louder than a helicopter and the only view is of the next door building a few feet away.
On the whole though would recommend if bland, personality-free chain hotels aren't your thing.
One tip if you're going any time soon, ask for a room on the right hand side of the hotel as the building on the left is being renovated so there is some construction noise from about 7.30/8am.