This is a unique product. I'm so happy someone decided to design this. It's very handy to be able to put my mixer (Mackie ProFx16v3) anywhere I want, in any situation. Recently I used it in a small show with different artists: spoken word, comedy, solo music acts. I myself was also one of the acts, playing/singing a few songs. But I also was the audio engineer that night. Thanks to this product I could easily roll the mixer next to me when I had to play. When the other artists where on stage I rolled the mixer to the front row to be able to do the sound from that position. I also use this in my studio/rehearsal room. It enables me to quickly switch my setup and move things around.
I also like the quality and the stability. It is very well made and I trust it to serve me many years.
The stability is very good with my mixer. Though I can't judge the usage with heavier equipment. It will depend on the height you set it to. The higher you go the more stability you loose of course.
All in all I think this piece will stay with me for many years. Very happy with it.