This was one of the coolest places I've been to in Japan. It is like a ramen-themed Disney land!
Once you get inside there are a number of shops to choose from. The awesome thing about it is that the shops are actual branches from famous ramen shops from all over Japan, so it is a great way to try different styles of ramen all in one place.
There are two different sizes to choose from at most places - a regular size and a sample size. We chose to do the sample sizes and eat at more places for the variety. In this way it is fun to compare the different styles.
If you get too full, don't worry! With a single entry fee you can actually leave and come back! If you are coming from Tokyo, a good plan is to go the museum for brunch/lunch, then spend most of your day in Yokohama. On your way back to Tokyo in the evening, you can stop at the museum again for dinner!