I don’t, but I’d like to try it.
Top tube length is really important if you’re looking at that ilk of bike Gotama, as you’d presumably be hoping to use a shortish stem, but still have a decent ‘all-day’ type body position
I can see being more stretched is good for racing, or an all-day in terms of a TDF stage, but why for a generic long ride?
The ultimate comfort bike for long rides would surely be a shopping bike – short with high bars. (I’m not proposing shopping bike fit for MTB, just questioning the wisdom that long is best).
EDIT on second thoughts don’t answer, too subjective & not what we’re here for!