I agree with wcj, as soon as someone tells me they are looking for a low APR, I tell them they are not ready to play in this credit card game. the cost and fees for the rewards cards are very high and only can be taken advantage of if you pay you bill in full on time every month. Someone who asks about an APR is thinking about carrying a balance. I would be happy to sign up for a card with a 35% apr if the signup bonus was great, but would not even consider a 0% APR unles the signup bonus is great.
If you always pay your bill in full and on time every month, the apr will be 0% forever on all these rewards cards.