The CMC is primarily aimed at lenses like the fixed zoom lens on the larger sensor compacts, like the Sony RX100 series. It will also work well with the 60mm and 45mm macro lenses in the m4/3 world.
The SMC is designed for a lens like the Nikon 105mm VR or Canon 100mm macro on an APS-C or FF SLR.
In general, closeup lenses are not useful on lenses like Nikon 60mm because you are already so close to the subject that you can't get much closer. It just so happens that in this case that you can get a little extra magnification with the CMC + Nikon 60mm, about 1.5:1 at 10mm working distance. Yes, 10mm.... that's pretty close. If the 60mm was your only lens, then I might say this is useful, but in my opinion, you are better off with the SMC on the 105mm.
For Canon APS-C shooters, the situation is a little different. In this case, the SMC is useful on both the Canon 100mm and the Canon EF-S 60mm macro lenses, but the CMC does not work with the EF-S 60mm macro.
Hope that helps,
I am wondering about the difference between Nauticam smc and cmc. I know that the smc can't be used on the 60 mm, but are there any other difference ?
I Use Nikon D7200 in Nauticam, and I have both then 60mm and 105mm macro lenses. Now i wonder which macro converter to get.
Any comment on this is most welcome.