This is my first pair of Keen's, and I'm impressed. The Alamosa is one of the most comfortable hiking shoes I have ever worn. It has two unique characteristics: it's wide in the fore-foot and it has a mesh tongue that doesn't bunch up and cause blisters. The shoe didn't require any breaking-in and it feels like a running shoe. Add top notch traction and Keen's waterproof system, and it's my new go-to shoe for day hikes and light backpacking. Thanks Keen!

A very good looking and comfortable shoe, aside from being a little short in the length. Needed 1/2 size larger.
Would have reordered next larger size, but were on backorder.
Returned shoe for credit.

I chose the Alamosa, size 9, after trying the Voyager (great toe room but not waterproof & lacing created pressure point) and Targhee (felt too constrictive; insole has more cushioning but that left less room for foot).
I have previously used the Vasque Breeze Mid, which I greatly liked but decided the ankle "support" was not needed.
I wear 8½ to 9. While the 8½ felt nice and snug, it did not leave any toe room. The 9 fits well. I have a fairly wide foot.
I wore the Alamosa on an 8-mile hike up a mountain (2800 vertical) and a 20 mile wilderness backpack (3000 vertical) on a good trail with some rocky spots. My arch was inflamed after the mountain hike but it went away after a couple of hours on the wilderness trail, and then returned halfway through the 9 mile hike out of the wilderness (but later went away).
The Alamosa does not seem to have much arch support, but my arches are getting stronger and I didn't need it (although the cause of my inflamed arch is still undetermined).
Traction was as good as I've ever had while hiking. The sole is rugged, but you can feel some of the sharper rocks. However, that wasn't a problem: it made me more nimble and sure of my footing.
I got drenched for 20 minutes one day. My feet stayed dry.
The tongue has a loop, which I find rather useless. Likewise the heel has a loop with goes sideways, not vertical, which I also find mostly useless. I use my thumb as a shoehorn.
My biggest disappointment is the ugly color. Mine is "Dark Shadow/Picante." But the leather appears GREEN! Whose idea was that?? It is not brown like the picture and the in-store display model.
Beauty is a relative thing: I find the rubber toe cap unappealing (albeit practical). Add the strange green color, and I find myself a bit embarrassed to wear these in public! (To each his own: many people consider the Keen styling to be a status symbol...)
While my feet were tired after a 20 mile pack trip, they were probably less tired than with any other boot I've had. I intend to use them for further backpacking, as I had no problem with support, but rather, felt quite sure-footed.