Similar to setting up for portraits at a dog show: the dogs themselves tend to be used to people, relatively well-trained and (generally) well-groomed. The effect of strobes on animals is always an issue and I would think it would be more difficult in general with cats.

As I said, first shoots are always a stressful situation. Glad you had a helper (really helps) and that you got such good images. As for getting bitten on the butt for giving away the sittings: I wouldn't be too concerned about it. The gamble you took is that you'd have good images to sell. From what we've seen, you certainly do. Plus, now you have some additional portfolio stuff. Nice job.

Jim