The Stache is a cool, unique bike, but Trek discontinued it years ago and the plus tire market has evaporated. The geometry also does not work for everyone - it's very terrain dependent. NSMB did a cool min-max article on the Stache awhile back:
https://nsmb.com/articles/min-max-ro...rek-stache-29/
As unique as they were, I wouldn't generally recommend it.