spamming the link is good, but it still does not get the correct eyes infront of the correct app tickbox.

apps installed from extras-testing should/could be added to a special list on the device.
then using the same "Updates available" ui, flash and solicit feedback directly on the device sometime after installation, or when the user goes back into the app manager "installed application" list.

"Its been 24hours since you installed uber widget, what do you think?"