Very good quality / price ratio in 1105

I do not think so much other adapter rings, but it seems to me quite sufficient to fill my need in this area. Obviously I have no perspective on the length, but for now my mount M lenses fit well and without play on the nex.
I was surprised initially by testing a goal, the concern I had was related to a screw to mount M-mount adapter that caused the game on this adapter ... So be careful what you use and quality adapter rings you use (including some exotic targets) prior to criminalize this adapter ring.
Similarly, on a gun mount lens M (yes, it exists), or the setting point scale is not centered but offset to the left. Again, this has nothing to do with this adapter ring.
So on Voigtlander type of goals, no worries for the moment, good flatness.
It remains true to make some further tests of development, but already to validate the feasibility of the devices and we can verify (or not) use manual lenses on a Sony Nex, this ring appears to me largely sufficient .