I don't know if they are different in the states, but I use Pampers Swaddlers. I like them. We are in size two, but I just bought Pampers Cruisers in size three on clearance. I bought the overnight ones (I think they were Baby Dry) and they leaked, whereas the Swaddlers never had.
I have a baby book called 1000 ways to save or something like that, and it said to help with overnight leaks, put a maxi pad inside baby's diaper. Will give you that extra absorbency overnight. Haven't tried it yet, but I thought I'd throw that idea out there.