In addition to what mankyd said, this printing method ties precision to the pixel density of the screen. Low resolution screens like the one you linked give lower quality prints. You would really need to step up to a higher-resolution small tablet or large phone (something like [1]) to get a package that works well for the average consumer. That's going to add at least $50 to the BOM and make overall development trickier.

[1] http://www.aliexpress.com/item/12/32579900233.html