Until 2 years ago, you could hardly give an XT away for shipping cost.
I have bought and sold a few when they were cheap. Like many people, I bought dirt-cheap XTs to see what the Model F mystique was all about, a Hagstrom converter (at 3x what I paid for the XT itself), later my Soarer's outboard converter, and concluded "Wow, what a great feel, what can I do to find something that I could actually use in real life?"
The XTant project really intrigues me, and I think that it could really happen if it could be cobbled together with parts stripped from original Model F keyboards. This would be strictly an enthusiast mod, with dozens (or possibly a very very few hundreds) of users, at best, but man-o-man what a great idea!
However, if F XT prices climb to the point that they are too valuable to strip for parts, the concept will probably languish.