Originally Posted by
cfwolfs
I've done both the museum of flight and the factory tour. I also up vote the museum.
I've also been to both. The Everett tour is not really impressive.
Everyone above has given great advice, including about the traffic, which can be very, very bad at any time of day.
At the Museum of Flight, in addition to seeing a wide variety of aircraft, you can also see on display an actual rock from the moon, something you don't see every day.