I loved my Chameleon Stretch 3s and after wearing them nearly everyday for two years, I wanted to get another pair as they were showing some wear. I tried the Chameleon Stretch 4s because the 3s were no longer available. I ended up returning them. The elastic on the tops which surround the ankle were just too tight. I was very sad to have to return them. I decided to try the Chameleon 5s, thinking that they would be just a lace up version of the Stretch. It turns out that they have a much firmer sole and are heavier. I think they would be very supportive for light backpacking. Ultimately, I think I will be returning them and keeping a pair of Oboz Men's Sawtooth Low BDry which are quite comparable, but seem to fit better.
This shoe is comparable to Keen's Targhee II, which I bought last year for some hiking and heavy duty walking when I went to Japan. I trekked in swampy areas and in the rain and my feet were completely dry. Due to the price difference, I would recommend the Targhee II's slightly over the Chameleon's.