My company is quoting a project in China vs in-house right now. Ironically, the parts are cheaper to make here, making the BOM about $2-3 cheaper. Yes our labor is probably minimally higher, but their price isn't including VAT or shipping costs. I believe the high price is because the vendor is farming most of the parts to outside vendors (adding middleman cost) and simply assembling everything in their factory.
The only reason we are on the fence is because their tooling is roughly half the cost of US tooling.
I've worked at companies before where everything was designed in America, but manufactured in China or Mexico.. and believe me, unless you have good management at either you will get crap quality. Being that pinball is really low volume compared to most industries, and the designs are cranked out so quick, and there are SO many parts to keep track of, it would be very hard to remotely assemble them. Like said above, only reason why it will work out for homepin is because the owner lives there and works in the factory every day.