I'm in the same situation as you. I don't want to fork out all the money for a new textbook but I also don't want to be disadvantaged by having the 6th edition, if that is the case.
well it was late round enrollment today and heaps of units were full. I was forced to ditch ISYS123 and pick up Accounting 1A and take up quite a few night classes. No complaints though, it might help with getting a part-time job