I knew a guy (vaguely) who flew one. The quote from the Beech owners club was always useful to wind him up;
Musketeers are not THAT much slower than 172s and Warriors, is the present version, I seem to remember it was less flattering a while ago!
His certainly seemed reluctant to get off the ground and less than spritely once airborne. I would think the 800 miles is pretty much a fairy tale. If I recall it struggled to keep up with a Pa22 (160) for speed, took twice the runway and burnt more fuel.
So that would be 95 - 100kts and over 30lts/hr which would make it a fair bit short in terms of endurance.
But if you can fly for 8 hours plus without a stop you're a better man than me!