C These unobstructed C telescopes are fantastic. Ditch your icky old Newtonian.
Try telling this to Parker and Miyazawa!
Frankly, it is very hard to beat good old Newtonian when it's well made/optimized. Especially in 10+ inch category, where it is prohibitory to use Fluorite/ED glass, and "ordinary" achromats suffer catastrophic chromatic aberration (unless made in ~f/50 range). Schefspieglers suffer from same tube current plague, large Maksutovs take forever to thermally equalize, and Shuppmans get just too big/complicated.
Dig out your Newtonians !
Bratislav
P.S. I'm planing to make an unobstructed (off-axis) 6" Maksutov-Newtonian, but more like an experiment - I don't expect it to beat good low-obstruction 8" Newtonian