Back to report on Wee Airic vs. Little Kippa (which I've taken to calling "Wee Mad Airic" in a Pratchett homage because I can't remember what it's actually called).
It seemed to inflate and deflate faster and hold the air better. We've always been very happy with the Wee Airic but the new model did seem to be an improvement in quality.
It is smaller, though; I think the Wee Airic was 126 x 51.5 x 2.5 cm, and the Little Kippa is 118 x 40 x 2.5 cm. The Airo 120, at 120 x 51 x 2.5 cm, is closer to the Wee Airic dimensions (although still shorter). So I probably wouldn't buy a Little Kippa for use by anyone over six or so.
On a side note, I don't seem to see a model in the current range that replaces the old regular Airic. The regular Airic was 180 x 64 x 4 cm (versus the Slim Airic's 180 x 51.5 x 3 cm and the Fat Airic's 202 x 62 x 7.3 cm), but in order to get a width over 51 cm now you need to go for the Dozer, as far as I can see. This is annoying as I am just coming to the conclusion that the Slim Airic is just too narrow for me and I could do with a 60 cm plus width, but I don't really want to add the bulk of a Dozer to my packing. I may have to look for a second-hand regular Airic or hold on and see if a better range of width options comes in in 2011.
[All sizes result of my Googling, rather than having an encyclopedic memory or crawling around with a tape measure, so I may have got some of the old sizes wrong]