Just to throw my two pence in !
I originally bought df64 and niche. It was a no brained to me and df64 went.
18 months later and still happy with niche but upgraditus kept kicking in and I really fancied flat burrs. Tried Major and loved it but way to large for my space.
Tried df83 and I’m delighted with it. Niche is gone now (saying that I would not hesitate for a second to buy another one as loved every minute of owning it).
With the df83 I changed the burrs to mazzer (can’t comment on originals as not used them at all), removed one of the declumpers and polished the chute with beeswax (thanks @tompoland).
Really pleased with it although it’s not really same price bracket as df64/Niche.