I downloaded Google Maps as a backup but honestly, Apple Maps has been pretty decent for me. The worst it has done is lead me on a longer route than necessary a few times (but even that seems to be diminishing over time).
By the time iOS7 is released, this is going to be a non-issue... and it's already a non-issue for some of us.
Still, options are good.
Or check out my new webcomic: http://selfcentent.com/