Each summer for the past few years, I have purchased several pairs of Columbia Nevi.  I live in them and find them extremely comfortable, even walking many miles at a time.  I typically have difficulty with new shoes and sandals but these are the first type of sandals that are comfortable right out of the box.  The newer model, Kea isn't quite as comfortable but still a great shoe. I've never had an issue with a sandal not being as expected. In March, I purchased 2 pairs, one in black.  The black pair has been in a box until I took them on a recent trip, never expecting there to be any issues.  I put them on one morning before a long day of walking and one heel didn't feel quite right but I assumed within a brief time they would be fine.  How wrong I was.  I was in agony within a short time.  The heel bed forced my ankle and foot to bend in an unnatural way and I was stuck wearing them for several hours.  Once I got back to the hotel and looked closely at the sandals, I realized that the sandal that was giving me difficulty looked very different - raised and curved differently - than the other sandal.  I regret not realizing this at the time of purchase and am now stuck with an unwearable pair of sandals.

Update:  July 2013, assuming that my purchase of the above-mentioned sandals was an anomaly, I ordered another pair of the Kea sandal.  While the heel of that one pair was a problem, I was able to comfortably fit into the sandal.  Not this time!  What has Columbia done to these sandals????  They are extremely tight over the top of the foot and I have to return them.  I have 20+ pairs of Columbia Nevis and Kea sandals and with the exception of the pair last summer, they are wonderful - fit well and comfortable.  Not anymore.  Very disappointed.