Top positive review
Great performance for the size and weight
Reviewed in India on 15 June 2020
Bought two sets of 2x MG90S motors to replace the lower priced SG90s in my projects. Here's my perspective after testing four of these servo motors.
1. These don't seem to be the original ' Tower Brand' MG90S, but considering their cost and performance, I would still recommend these unless torque and fine accuracy are an absolute must (in that case, you should be buying more expensive and larger servos).
2. The movement is very smooth and the servo makes very less noise compared to the SG90. Three out of the four that I bought made minimum noise, the fourth one seemed a little off and was slightly noise, maybe a case of internal gear friction or less lubricant oil. But even this motor was reasonably accurate in positioning, although relatively noisy.
3. The SG90s costs Rs99-150 as on June 2020, this motor costs significantly more. It will increase the overall cost of your bill of materials.
4. These motors don't swivel a full 180 degrees, more like 160-170 degrees, which is normal for most servos in this range. The SG90S, on the other hand, can be clocked (beyond the 1-2ms PWM range) to achieve a good 180 degrees control. I saw another review of someone else claiming to move the whole 360 degrees -- well, mine didn't make it to 180. I will buy another set for testing and update my review after that.
To summarise, I would still recommend the SG90S which is lighter and cheaper -- if your hobby model doesn't require high torque or accurate positioning (the nylon/polycarbonate gears of the SG90 sometimes skip a tooth if subject to rough usage), or if weight is a factor to be considered (such as in drones or RC airplanes).
But if your priority to to have a light weight and rugged mini servo, this is by far the best choice.