I bought this amp stand to avoid bothering venue owners in finding beer kegs, chairs, or other strange devices to raise my own amp from the floor.
Well, this stand is really not suitable for the job, and has more cons than pros:
1) it is not really that stable.
2) it can hold only VERY light amplifiers and it collapsed as soon as I put a heavier amp on the stand (but still a 1x12'' combo, nothing huge)
3) This happens because the "locking" mechanism is damn fragile. It relies on two gear-like wheels with interlocking little "teeths"; as soon as a wheel has a slight distortion or becomes slighttly out-of-axis with the other, the stand collapses with some weight. Maybe grinding away some of the teeths in the process, which makes it even more unstable.
4) when folded, keep in mind that it still occupies some space because of the L-shaped rods (I've seen better mechanisms)
As for now the stand has become pretty useless, I use it only sparingly with a neodymium-cone 1x12 speaker (ultra-light 5kg speaker) or to hold a little 12 channel mixer.