In a few weeks time I'm off to cycle around Oz for a year - seeing as there's a reciprocal health agreement with UK is there much point in getting insurance? What are the pro's and cons?
My belongings are worth maybe £2500 including the bike (which aren't usually covered to full cost) but it could cost me a fifth of that in a premium. ...


To be honest i didnt.
Do make sure you sort your medicare card when you get to Oz though.
I had the briefest of cover from booking my ticket with my credit card and my ticket home allowed 1 free date change, so I was covered if I had to leave early for any reason.
But the cost of a years cover just didnt seem worth it for me and I luckily didnt need it.
Good luck with your trip, you seem a lot more prepared than a chap i met who got as far as the outskirts of sydney before his bike broke and he gave up on the cycling.

As well as belongings and medical cover in Australia, insurance will pay for you to be flown home in special medical circumstances, eg. if you are severly injured and need special care on the flight. You will also have cover if you need medical treatment on any stopovers you might take.
If none of these matter, you can probably get away without it.