I saw somewhere recently that open-backed headphones were recommended for mixing - I currently have a closed-back set. Apparently, open-backed provide a more authentic, natural sound of what you're hearing, and what do you think of headphones compared to studio monitors - or do you use both?

Those forum members that spend a bit more time mixing or have more mixing experience than I - is there a benefit? If so, what would you recommend? I am on a retired budget, so recommendations under AUD$300 (US/EU/UK 200).
Thanks in advance.
Andrew D