I beat the campaign (normal) the first day. Played some mp, FireFight, Forged a little bit and saved a couple films. Now I'm playing through the campaign on Heroic.
I have nearly 75,000 credits (I think) and I'm saving them for the electricity Armor Effect, which is 2,000,000 credits. I'm thinking I'll have it in about 4 to 5 months hopefully.