Thanks for the replies. Yeah, that's why I went for physical gold to build up a reserve at the beginning. The predictions of collapse of Western Banking were so hot at the time that I wouldn't trust ETFs.
But it seems to me that such a global collapse has receded now. There may still be risk for individual European banks in particular, but nobody serious is talking about a systemic problem which could bring down the whole system any more, and Asian Banks are among the strongest. I have no big worries about HSBC in particular.
So, rather than just buying physical and vaulting it I see benefits in having ETFs for the same reason as China Flyer. Mainly to do with trading and buying into short rallies. It's an entirely different play from stocking up on the physical.
So, if nobody thinks HSBC are too expensive, or otherwise untrustworthy (hah, a Bank, untrustworthy!) then I may take a punt.