But 1.0 and 2.0 both fire an event when the override is set?
1.0 possibly, but it relies on Ace2.
2.0 does not fire _any_ events (because it does not rely on any event library), and does not provide _any_ callbacks for that matter.
I was just saying that 3.0 currently is the best (as in, most complete) library for the task, unless you want the Ace2 dep and get 1.0
If you read my first post on this topic, i already said that i never understood why 2.0 wasnt "fixed", because the API seems pretty straight forward + additional callbacks. I'm only stating, that 3.0 is right now the best choice, feature wise.
Oh because the callbacks are pretty important, without them your addon might end up in limbo using the default texture, because your texture might not have been present at load time, or simply ignore a global override texture.
Plus 3.0 validates fonts if they work with the asian WoW versions.