If by cheat, we mean not just codes, but walkthroughs as well, then I'll definitely cheat before I quit (I mean, I bought the game, I want my money's worth, at least to get through the story). More often than not, I'll just put the game down for a while, sometimes several months or even years, before I pick it back up again. Strangely, that tends to work more often than not, even if I haven't been working out a strategy in the meantime; Maybe it's just to do with mindset. If however, putting it to bed for a short time doesn't change things, then I'll go to the guides.