I agree with jcap.

I don't use devmode for unfair advantages. On all PC games I play, I beat the campaign the honest way on hardest difficulty. Then I come back with cheat codes for a funny way to play. e.g. using nothing but the crowbar in Half-Life, blowing through Covenant using a bottomless plasma gun, jumping to places I'm not supposed to go, etc - you can't deny it's fun after you've beaten the game!