Well, having looked about a bit further and getting a few more answers in the Belgian iPhone thread I started, that even though I'm currently Aus at the moment, which with some minor hoop jumping I could manage a purchase of an unlocked phone, I'm going to wait til I can get to Belgium or Italy to buy a factory unlocked iPhone. Belgium and to a lesser extent Italy are close enough to the UK that I can get there fairly cheaply if I need to have work done by or exchange phones with Apple on the iPhone.
With so many reports of cracks in cases, broken pixels, and people saying to wait for 9/9 to see if there's some bug fixes, it's not going to hurt me to keep using cheap SIMS for another month or two, not if I end up with a phone I can use with international SIMS AND what will essentially be a mini computer, allowing me to email and post to my blog when I'm not at one of my home bases in the US or the UK, without having to haul along my MacBook on each and every trip.