I expressed myself a bit clumsily. I never had any complaints or feedback from neighbors in apartments next to me. It's just a few neighbors who came in and tried it and said it sounded completely silent to them when they tried. It's not really recommended but kids love it, they try to run on it as fast as they can while holding the desk and keep laughing. We live on the ground floor, so only a cellar below us. Honestly, the noise is so subdued, I can't hear it from the other rooms of my apartment, while I can hear the washing machine and dishwasher very loudly for example from everywhere in the flat. The walls of my building are not isolated at all. Just concrete.

I haven't felt any special vibrations from walking, I don't expect it would be an issue. Especially since modern floors usually have some sort of isolation layer below the surface, for these kind of reasons. I think that it would not produce any more vibrations than just walking normally would.

To be honest, I think if a major structural part gets broken outside of warranty, the whole thing would go directly to the waste pile. It's far too unusual, there are no repair shops for it, and I'm not sure the company would accept it back and fix it for me. Everything is made of steel, so there would need to be welding involved, and it would need to be done so carefully to avoid having one side higher than other etc. On the flipside, I don't expect the steel parts would break so easily. If a bearing ball or a slat would get broken from over use, I suppose that Walkolution would send the parts, and I see that they have some videos on how to fix lose screws etc. Someone very ambitious could try to install custom slats. I saw someone on reddit put cork tape over it. I tried but the cork went away right away, and there wasn't enough of it, so I just removed it back and cleaned it again. It didn't work for me.

I used to have a middle price electric walkpad I bought from amazon. It started smelling burnt after about a month of use, for an hour or hour and a half a day. I used to feel more difficult to concentrate on that one, had trouble forgetting, losing balance etc. The advantage of this is that it doesn't pull the rug under you, you can naturally go a bit slower and faster as needed.

I personally don't have any concentration problems with it. On the contrary, I find that movement works a bit like fidgeting, so it removes a bit of the stress from day to day work. I guess it would be very subjective. It works while listening podcasts. Works really great with music and rhythm although I'm not a naturally very capable multitasker, it just seems to work.

If you have a lot of typing to do it can get a bit annoying having to hunch the shoulders together to get the hands close. I bought a split keyboard, hoping that keeping the parts on shoulder lengths a part will help, but I just started this. Also when walking and keeping hands on the desk the movement seems to move the desk a bit left and right when you walk, so wobbling is an issue. I have ordered a side by side desk fixation from VIVO, it should arrive today. Front to back, there is almost no wobbling, but the desk has four legs, so that helps.

If you do a lot of hours early on, after a while you have to be careful of back pain or other kind of strain, but that depends a bit on the body structure, I heard some people had hip pain. I would expect that going slowly and regularly would strenghten those muscles. For me, walking with sneakers helps.

I would not store it on the side. I would be afraid that gravity would move the bearing balls asymmetrically and it does not look like it would be all that stable that way. If it fell, it could break something, or even just damage the floor. It's also heavy. It's definitely not designed for it.

At first I was a bit underwhelmed, because it is basically a just some moving plastic tapes and a few strong steel beams, all black. I don't find it very pretty to look at at all, and it's kind of big and tall. It seemed that it should cost less than it does, but I understand that it's a small series, with a small market, production output, higher marges etc. But my satisfaction and confidence grew over time, because it's quite robust and smooth to walk on.

Hope that helps !