Hello,
 
We have a 26 frame and it seems to work great.  A few cautions though, watch
out for newer comb, it will rip those babies to bits.  We had difficulty with
toofast of a start up speed and Cowen has some sort of variable speed adpter
we are going to install.  Any granualted frames will also come apart.  We are
very satisfied overall with our machine.  Cowen's plant is located down where
my dad grew up so we are down there once or twice a year.
 
Good luck, and I hope the extractor gets lots of use.
 
 
Derk