Product Red can be better by not existing
First, both Apple and Bono can simply both donate $70 million in pocket change to any charity they want, so arguing about a gimmick like (Product) Red just makes them both look like *******s.
Second, Apple can do more for (Product) Red by ending the relationship and instead just donating $1 for every device sold and ask people at checkout which of, say, 10 noble charities they would like that $1 to go towards. Heck why not give $10 of Apple's excessive profit margin per device away to charities. Why ask consumers to buy a specific version of only a few specific products when the company can part with far more money to charity otherwise.
I think Apple could generate far more than $70 million for AIDS research, but also generate a heck of a lot of revenue to other charities, you know, maybe like cancer research?
It would be nice for Apple to become a little more openly charitable in general rather than relying on gimmicky product tie-ins for a color of a product nobody really wants.