Living in Beijing, I'm so bored of cybermarts. Also, if you want to find the makers here, try wangjing and CAFA (central academy of fine arts) rather than Zhongguancun (where all the e-markets and grand tech universities are). It should not be surprising that the designers and artists would be more passionate about this than the engineer/entrepreneurs/traders trying to make some bucks.
Also, never leave your computer with the solder guy; always insist on watching the repair. They have swapped out good components for broken ones before.