Can you link to the sandals you’re talking about? Only thing that comes up for me are the misspelling of chanclas, the generic word for sandals in spanish.
My family is a bit of a Chaco cult. We've climbed 14'ers in Colorado in them, my sister wore Chacos under her wedding dress, and I unintentionally ended up living and working close to the HQ.
I personally have walked 10 miles in a pair, but it was pretty casual walking.
Get them on sale, and send them in to get refurbished from time-to-time. They are fantastic.
I have a pair and as an avid hiker and trail runner... I'm not sure I'd walk 15-20 miles in them. I have other better-suited footwear for that!