I have had the machine for a month. I haven't used it much, nor am I a professional, of course. The build quality seems very good. It doesn't give you the impression that it will fall apart. The handles are satisfactory, with soft plastic grips so they don't cut your hands, which they do satisfactorily (although they could be better).

I don't know what role the arms play and if they really help, given that they are simply attached to the body of the machine, without being connected to the pedals in any way, to provide some significant resistance. In reality, they just guide the movement of the body. In general, they add more bulk to the machine and make it more difficult to transport. Also, the attachment of the arm pieces is not very stable and the arm "plays" a little, but fortunately without causing any problems.

The instructions don't say anything significant. They could provide assembly instructions with much greater detail and have better images.

Overall, a mini stepper is really value for money and it's worth getting a good quality stepper. I consider this one to be of good quality, but it definitely isn't worth 120 euros. For 70 (max 80), it is very good.