THESE DO NOT HAVE METAL GEARS!!! The last gear is metal, the rest are grey plastic. These are not MG90s. They may be OK for small foam models, but they have PLASTIC GEARS. I had to give them 5 stars because BG wouldn't show this review.

Ordered 12 of these, this is the first batch of 6. Out of the 6 I got, 3 work really well, they are accurate, relatively quiet and center well enough. Unfortunately, the other three are not so flawless. They are much noisier and even though their movement seems fine for now, they constantly buzz. These also seem to center... well not so much at the center. They are stop a bit off on one side. But they do work, I guess. Hopefully, the won't die on me in an hour or something. In summary, they seem to be fine for applications where accuracy and silent operation are not your main goals, but if you want these for precision applications, they definitely are a gamble.