Wow, thank you all kindly for your responses and advice. I really liked the finishes of the Columbus, especially that you get corian on the bathrooms in addition to the kitchen. I also really liked the one piece fiberglass shower in the columbus. However if the slides are an issue, that can tilt things in favor of the Silverback. I wish the silverback had a microwave in the outdoor kitchen but I can always live with that. I like the sandpiper/sierra but don't know much about the frame/wall construction versus the Silverback and Columbus.
Thanks again. Keep the comments, advice, opinions coming.
