I have traveled with two Oriental Shorthair cats, related to Siamese, and have previously owned (or been owned by) a wonderful full-blooded Siamese. I'm sure you already know that they have strong personalities and vocalize often. Our cats adapted very easily to travel in the RV, and quickly found their favorite spots for travel and napping. We were also able to train them to walk outdoors wearing harnesses and a leash. Cats are good travel companions when they are happy. It's your job to figure out what will make them content. Start with bringing along their favorite bedding, litter box, toys and food. One of our cats is more fearful of traveling than the other, and likes to hide in a small place when we are moving. He will either climb up under our recliner or go into his cat carrier, which we leave under the table with the door open. If you have cats who try to hide during travel, just make sure they are not in a place where they could get injured. Sometimes, it's just safer to crate them until moving time is over.