I've only bought a few things from Alibaba over the years, but most of them have turned out to be either faulty or a typical case of 'chinese manufacturer disappointment' which has led me to being reluctant to buy anything larger/more expensive. When I was in Marrakech a couple of years ago, the guy who owned the riad we stayed in referred to many things in the souks as being "China quality", and I guess that's the problem. I don't expect something for nothing, but it's so hard to tell if you're going to get something that's going to be as I would expect (i.e. functional, accurately manufaturered), or as I've experienced (borderline functional, poorly manufactured or badly designed). The best purchase was a secondhand (rare) motherboard for a client's laptop, sadly!
It's a real pity as I'm sure if there was a way of really knowing the quality of what you were getting (other than getting samples, which I've done and had issues with several of them) then it would be a great place to buy either for personal consumption or for a business opportunity. At times like today I spend a while browsing and see things I would be interested in if I wasn't concerned they would be 'China quality'.
Am I missing something here? Is there a better way of sorting the wheat from the chaff? Or is it just a case of a lot of hit and miss and hopefully building a relationship with a decent supplier at some point?