There has been a lot of discussion on the forums about the 7Artisans 50mm f/1.1 lens for Leica M lens. Mostly because it's cheap. Around £300. The Voigtlander Nokton f/1.1 is around twice this and of course the Leica M 50mm f/0.95 Noctilux is around £8-9000. So a fast lens that could be used on a variety of systems, some via adapter, what's not to like? Or is this too good to be true? Well actually the second possibility seems to be the case. Mine broke.
I ordered this lens via Amazon and it arrived from China after about a week. After trying a few test shots the focusing ring became detached from the lens. See below.
So no prizes for quality control then. In the Leica Rumors forums lot's of people ordered the lens and didn't have any problems with it. However one person indicated that it wouldn't go to infinity which is how my lens started with it's problems. I agree with the majority of the contributors in the forum that the lens is a decent performer. From the few pictures I was able to shoot with it, it was pretty sharp even at f/1.1. However it's difficult to get past the fact that the lens broke on me after a few minutes use. Now I got my refund and postage back, but I for one will not be buying anything ever again from this company. True, I've had a Leica lens break on me, but after a fair amount of use, not straight out of the box.
So if you have seen this lens and think it may be for you, all I can say is that it seems there is a certain risk of getting a bad one one. And whether that matters to you only you can decide.