One of the things you are after is better resolution. In that case mono might be better. I've been using the STC duo for a while now, and to really get full bang I've found that you have to superpixel debayer to get good colour separation
- see
https://www.cloudynights.com/topic/6...4#entry9649949
That really reduces resolution.
Regarding your image, it's also best to split the channels and process them separately to stop the red Ha dominating.
Also, given what I get with the duo/OSC my 'impression' is that real NB with mono will 'look' better. I know this sounds a bit vague but you are looking at a big investment