On this trip to the beach, I tried three varieties of American weissbier.
The tale o' the tape:
Surprisingly good, in fact excellent: Sierra Nevada "Kellerweis" Hefeweizen. Much, much better than I expected. Looks and tastes just like wiessbier, in fact. Well done. My new favorite, #1 American beer.
Surprisingly good, because it is not horrible: Michelob Dunkel Weiss. Again, much, much better than I expected. Not actually great, just better than I expected. If you are stuck, this beer will in some ways remind you of a real dunkel. For an An-Busch product, outstanding, though.
Surprisingly bad, bordering on terrible: Sam Adams Weiss. Awful. Appalling. Why did they even try? Tastes like a generic beer, no head, clear amber appearance. Supposedly "retired" (i.e., discontinued to end the sucking), but still available.