I decided to get the Stowaway and flattener because I want to get started with imaging built around a reasonably fast and highly capable but portable triplet. Given that I have a 3" and two 4" refractors, I would likely have passed on the Stowaway were it not for this intended use. But then again it is tough to pass up an A-P so, truth be told, the imaging intention helps with the justification. I have the FC100-DL and to me, this represents a great complement to the Stowaway as a longer focal length visual instrument. My 3" scope (TV-76) is now my most vulnerable and whether I keep it or not will depend on whether I can get a screw on adapter (looks like I can) that will let my mount my solar filters on the Stowaway.
Don't know if that helps but it does seem like the SV80 would be a bit superfluous if you got the Stowaway. For lunar and planetary - I'd give the FC100-DL a good look and maybe hold onto the SV80 for wide field.
Edited by Doug D., 13 February 2020 - 02:23 PM.