Hey Zookie,
I owned 2 of the original 50 cal Buckwacka's that were completely made in the USA. I believe that the newer ones have the receivers made in Brazil and are assembled in the USA. I ended up giving one to a friend and still have the other. They were both comparable with good fit and finish, but I had to do a trigger job on one of them. They use the same scope bases as the round receiver Knights.
The MDM's have fast twist barrels (1 in 24") and thus I have found the best accuracy with long, heavy for caliber bullets with appropriate sabots (250gr 40 cal, 300gr 44 cal, 300+ 45 cal and 400-450gr conicals). Recoil can be stout with heavy loads so you would have to experiment to find a load that suites your needs.
If you like the features of the MDM, they are functional and easy to strip down for cleaning. I haven't priced them recently so there may be more attractive options available.
Regards.
