Finally got the MF8 FT Starminx in black!

So, I haven't tried solving it yet, but I just want to check before I begin: on the Rex Cube, which is a bit similar, if you try to solve into its mirror image you will end up with an impossible situation. Does the same happen here? I didn't memorize the color scheme before scrambling...

No, and not even because of an impossible situation. If you look at two faces opposite, say white and yellow, the five adjacent faces to each are different, so the five edges of each are different as well, and cannot be on the opposite face. Because a rex cube is a cube, two opposite faces are adjacent to the same faces, so it's possible for the edges to be swapped.

Edit: Ignore what I just said. I wasn't thinking right. I somehow forgot about the floating centres moving around.

Callum

Callum's response confuses me so here is mine.

The answer is no. The mirror image requires an odd number of swaps of the edges which introduces a parity in the edges. Other than these two edges swapped, the whole rest of the puzzle can be put in the mirror image.

So, when I'm solving the edges, if I get two swapped, I have to start over? Bummer... I'll have to memorize it next time.

You don't have to memorize the whole color scheme. You only have to remember two sets of 3 colors and their relation to each other. Pick the groups so that the first uses the top face as one of the colors and the second group uses the bottom face (opposite the top) as one of the colors. Then, for the other two colors you only have to remember which is right of the other.

So using Gelatinbrain's color scheme, if I pick the white-brown-lightblue corner then I only have to remember that lightblue is "right of" brown. For the second group, if I pick yellow-red-darkblue then I have to remember darkblue is "right of" red.

This is enough to remove the ambiguities in the color scheme.