Signing up and playing on a poker room with rakeback is NEVER a bad idea. Full Tilt rivals Stars in its number of tournaments, SNGs, and the variety of cash games that are available, so if you can make a dollar or two per week in rakeback that equates to a full buy-in at the $.01/$.02 tables which can be very significant to bankroll growth.
One thing to keep in mind is that when you are registering on a new poker room, you need to be sure to clear all of your browsers cookies and register and create your account directly through us:
Full Tilt Poker Rakeback
Also, when it comes to PokerStars you will not be able to earn close to the amount of rakeback/valueback that you could on Full Tilt or DoylesRoom unless you hit the Supernova level, which takes some serious grinding at high stakes.