After getting over how long maps could be compared to other games, it became a good time. It might be harder to hit 100% of your shots, but you get so much ammo that it doesn't really matter. As long as you understand you're supposed to use the shotgun as practically a melee weapon, it clicks with you. I love how hidden some of these keys are, being almost more obscure than secrets in other games, and then in another map they have like 11 secrets, with half of them just being in random plain areas.