Sorry can't help. I'm a big chicken when it comes to pressure cookers. At least it's one thing I won't want in the kitchen.
Thank you for your advice. I am buying it for my mum who is 82. Which, in you opinion, is easier to use? She is technophobe... it has to be really simple, easy to use and preferably not too heavy.
Bonsai, thanks for posting the hip pressure cooking link. I recently bought a Kuhn Rikon pressure cooker and it's still in it's box unopened and in the cellar. The Kuhn Rikon pressure cooker got a good review, when I get back from vacation I'm going to start using it! It was one of those buys that was not totally planned, I had just been reading Hester Blumenthal's book (he is a big fan of pressure cookers for sauces), and Migros's were offering 50% off KR pressure cookers. I couldn't resist the bargain.