I've got an Ixus 500, there is setting in the menu called Quick Shot which you can set. However I've found it very fast in either mode, startup is quick too. It also has a fast shutter mode which will fire off a load of shots in quick sucession which get buffered up and written to the CF card.

The 700 looks good, the bit that looks really cool is the 60FPS slowmo video capture mode.

As for the CF card, I just bought a 1GB card from Scan for about £40, seems fine.