It's a crap shoot, really. The bass you see in the picture is almost guaranteed not to be the bass you receive. As well, it's impossible to tell what condition the frets are in, whether the neck is warped, and if the electronics even work. As well, the shipping costs make it almost impossible to return for a new product with the same lack of guarantee about the final quality.
If you have patience to fix some of these yourself, I don't doubt that there are plenty of no-name instruments on there that are worth the time and certainly money. I'll probably purchase a future no-name bass from eBay and mod it within the next year. That's my style, though.
The ebay(ish) brands that I come to mind and are generally of decent quality - SX/Douglas/Brice and BassMods.