My DSI RC10C + QSI683wsg-8 mono, give me 0.6 as/pix. A major downside is the 33x25 arc min FOV so that the larger DSO's, M42, Rosette, Omega Cen etc., have to be built as mosaics, taking that much longer to acquire. The Rosette for example is a huge 16 frame so 16 times longer to get sufficient data. At 75 I might not live that long!
Charles