Right now, doing the part time job will net you a ton of credits for little to no work.
In fact, part time work is the only optimal was to get money in the early game because when you convert Peepcoins to actual currency, you either have to metagame and make sure you convert the coins before the delivery day (wednesday) or wait for another week for the next delivery.
I hope Moondev will give us two deliveries per week instead of one at some point.