G'day and welcome from an old Newcastle lad. Whereabouts in OZ are you from?
Some, but by no means all, early RIIIs had a problem with jumping out of 2nd gear on HARD acceleration. The update kit fixed this, and while they were in there, a few other things were also updated. If the bike you are looking at has a few miles on it, and doesn't jump out of 2nd at WOT, then it is probably okay. Ask the owner about the update kit or any issues similar to that.
The thing to be careful, especially if you haven't ridden for a few years, is that this is a big, heavy, and powerful bike. You have never ridden anything like it before, so be very, very careful.