[gregbradley]

I think that should Qhy294M versus ASI 2600 or WHY268.

Read some poor customer service and QC reports about ZWO.

I have the 294M and the QHY600M.

They are both very sensitive cameras. The 294 has 4.6 micron pixels (from memory) which are 2x2 binned out of smaller subpixels.
But it has some amp glow which does calibrate out but it means your calibration files need to be good and matching.

The 2600 is similar to the QHY600m just a smaller version of it. I find it handles much the same as CCD cameras and is not that fussy.

On some scopes you probably don't need darks nor flats. You will with the 294 mono.

I haven't used the 294 for a while but neither do I want to sell it. I'll put it to use at some point.

The usual reason someone would not get the larger sensor is to avoid having to buy larger filters which you already have.

Greg.