Hi selling a Intes Micro MN56 5” F6 Maksutov-Newtonian OTA {specs found here comes with soft case and dew shield. Only used three times asking $1100 plus post.
Hough,
if it helps to further your question.
The MN series is a great way to get apo quality at newt prices. You already know this as you have the Mak/Cass variant, but the MN is f6, and therefore very suited to DSO imaging. There is also a school of thought that suggests the MN's are better for lunar/planetary as well, due the smaller (~20% C/O).
When I had an MN76 (similar, just larger), I acheived enough in-focus by shifting the primary further away from the cell with longer collimation screws. I also shifted the secondary towards the primary by sliding the adjustable focuser base as far aft as it would go, and adjusted the secondary aft as well, to match.
This and a better quality lower profile focuser fixed all the in focus issues, and gave spectacular results.
If I wasn't strapped with my latest mount acquisition I would be grabbing this from Stuart.