I've bought heaps of stuff from DX. Certainly trustworthy, but in terms of product quality, you get what you pay for. Usually, the tradeoff is in reliability and construction. Obviously, DX aren't the manufacturer, just the retailer, so there's quite a variation in how worthwhile their products are.
The cheap flashlights all fail sooner or later - the switches in particular tend to break. DX do sell cheap switch assemblies, though, if you were inclined to fix it
To be honest, I wouldn't buy any more cheap lights; I'd put my money into something more reliable.
I have a couple of their little cheap gorillapods and they're much like the real thing, but perhaps a cheaper grade of plastic. No regrets here, these are great for holding flashlights.