Couver gets along with my cats really well, but it could be the fact that they have grown up together... Couver likes to play with them, and the cats usually seem to enjoy it.
If you are planning on having a cat, I would suggest getting it asap so they get used to eachother soon. I don't know how introducing cats to older dogs would do... I'm sure they would be fine, but it might take them longer, or they may not have the bond that mine do
