I only use a walkthrough from Gamefaqs when it's absolutely necessary. For example, to get the secret ending in Warrior Within, I needed to know the locations of the special fountains, so I used a FAQ for that. Or when I've tried something again and again and again without success, I consult a FAQ. Just as a last resource or for a secret.

Also, I never use cheats. Ever. It ruins a game IMO.