I was just at the RB Amsterdam for 4 nights, four rooms total. It was a very good experience, great location, very helpful staff (concierge was great at restaurant recs), good (albeit expensive) breakfast buffet, and a nice bar for late drinks. I have no idea where the other hotels are, but I was very pleased with the Blu and would happily stay there again.

Also, if you want some really good traditional Dutch food, we had a fantastic meal at Restaurant Greetje. Delicious food and a great waiter.