My brother did and he hated it. ALways a problem getting a car when he needed it. Problem is, everyone in NYC wants a car on the weekend and no one wants it during the week. He went back to renting cars the old fashioned way despite the high costs.
Wow, that looks like a really cool service. I'd never heard of it before now. I'm sure it will get better as it's been out longer. I sure wish they had that when I lived in Chicago...