To answer your question, it's a bit subjective so best try each combo and see what you like the look of yourself.
I've found Carbon 18.3-61.1.123 better than .155 so that's what I've used in my tests.
This is my thoughts on the following software combos:
- Carbon 18.2, SS3D 18.2 <- Too much noise, too coarse and grainy
- Carbon 18.2, SS3D 18.3 <- My preference for detail/clarity and better contrast for finding fish
- Carbon 18.3, SS3D 18.2 <- Too much noise, Too coarse and grainy
- Carbon 18.3, SS3D 18.3 <- Second choice, almost as good detail/clarity once contrast dialed down to about -10
- Carbon 19.1, SS3D 18.3 <- Its ok but noticeably detail/clarity not as good as Carbon 18.2 or 18.3
- Carbon 19.1, SS3D 19.1 <- Possible choice if dial contrast up +10. Range looked a bit reduced out to sides though. (Needs further testing to rule out or recommend)
- Carbon 18.3, SS3D 19.1 <- I haven't tested/ A comment above said it looks quite good, but no screenshots were posted? (Needs testing to rule out or recommend)
If you need livesight you'll have to use Carbon 19.1.
If you just want the new menu structure and good images use 18.3/18.3 and turn contrast down -8 to -10
If you just want the best images Carbon 18.2/ SS3D 18.3 seems to have a very slight edge.
Just my thoughts, I'm still tinkering with all the different software.