I've owned three of these, and only one of them is still usable. I had them for rehearsal use and a very rare gig, and they just weren't reliable.
We showed up to play a birthday party with two of them, and one of them literally fell apart. And I must add, I'm quite gentle with my gear - so I don't know what would happen if you treat your gear roughly.
The one which remains has had very little use, to be honest I'm half afraid to use it.
It seems a great option for us people on a low budget, but really spend a bit extra and go for a more expensive one. It'll be worth it. I've to buy completely new ones so if anything it's cost me more money by buying these.