All the discussion in the http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/27785106.cfm tread has been interesting. To me, it all boiled down to sure the truck can handle an over-weight camper ...
rickeoni, that looks like I-90 from last weekend between Snoqualmie Pass and Easton! With an exception of a very short stretch just after the pass that was super smooth.