I made a similar move from Canon to Pentax K-5 and a 645D. It made no sense to continue to hold onto one Canon body as a backup, with different menus, etc. The K-5 is a perfect complement to the 645D in terms of ergonomics and menu structure.
The unfortunate thing about photographic retail sales stores in the US is that the situation mimics the demise of consumer electronics brick and mortar specialists. There are only big box stores (Best Buy, Walmart, Costco) in many parts of the country. Canon and Nikon are prepared to make huge concessions to the big box stores to get their products on the shelves. I think Pentax is not in such a position.
All that said, unless you have gorilla-sized hands, I think you will love the K-5, even if you have to buy it sight unseen. I bought mine from Amazon, knowing I could return for full credit if I did not like it. Pretty hard to go wrong that way. Although I must admit, after having shot Pentax medium format film cameras for years, I had faith in the products because of my positive prior experience. So far, the digital products seem to be working great.
Last edited by CDW; 06-09-2011 at 01:53 PM.