I've done both whale watching in Juneau and the Bering Sea Crab boat. They are VERY different tours, you will not think on the second one "boy, we just did this". On the whale watching, you are caught up in the scenery until you find a whale -- then it is all about wildlife viewing. On the crab boat tour, it is all about the crew explaining how crab boats operate, the different types of crabs (and you get to see them pull in the net for several varieties and see the crabs up close). While you can view the scenery while the crab boat moves from spot to spot, you don't go too far and it more about the activities then the scenery. (We didn't do the dinner option either and when we were done with the tour, we were glad we didn't. The tour was nice but it was very nice to also have some time to do something else downtown.)