I haven’t actually owned either, so this is somewhat limited as feedback. I tried out the Mollenhauer in a shop and it is a lovely instrument. In the end, I actually bought a Moeck instrument, but the Renaissance Consort model rather than the Kynsecker, because I wanted to try the renaissance fingering rather than baroque. I think all the Moecks are stained pearwood rather than plum. The staining on the RC model looks better than on the Kynsecker imho, but to be honest I don’t think the wood (contrary to lots of counter claims, so just my opinion) makes any difference at all to the sound, it’s just about the look. Not that that doesn’t matter.
Something you might want to think about if you haven’t already taken the plunge – I only just saw this – is differences in fingerings. This is solely about my limitations as a player, but I find substantially different fingerings easier to come to grips with than fingerings that are almost, but not quite, standard. That’s partly why I chose the RC. Both Moeck and Mollenhauer have fingering charts online, and both show various subtle variations from standard baroque fingering.
If you have already bought one, I hope you are enjoying it. Let us know how it goes!