I have a good friend doing arts (psych) at Monash and intending to go into honours, and later becoming a psychologist. From what she's said, psychology through arts is better because then you can take other semi-relevant subjects. For example, she's doing minors in sociology and criminology, which have given her a broader perspective.
She has spoken a LOT about the difficulty and workload of the course. I do law - typically a writing/reading-intensive course - and in comparison, she has just as much reading as I do, and about 10x more essays. However, having heard her talk about some of the stuff she's studying, it all sounds really really fascinating.
If you have any specific questions about the course I'm happy to ask her for you.