Have been looking at the Lexar 512, but I'm wondering about the difference between the standard type that I already use in a Kodak camera and the 32x high speed one. Is the high speed one a lot better? I'm a very ordinary photographer!!

Hi there,
By "ordinary" I suppose you mean you don't take hundreds of shots at a time.

Personally, I'm not convinced that a really high speed card will make that much a difference for the majority of FZ3 users. I didn't buy one. I have two PNY secure digital cards in my FZ3 and I'm very, very pleased. The camera is quite responsive even when photographing (or at least trying to photograph) birds in flight, one of my favorite and most challenging subjects.
Lexar and Sandisk make reliable cards.