Hi there. My husband (Andy) and I are moving from NC to NM in a month or so with our two cats. The way his job relocation works is that we only get compensated if we drive, so I can't just pop the kitties into their soft-sided carriers and bring them as under-the-seat luggage on an airplane. We've done this with the older cat, Thena, on two summer internships to California, and flying with her was much easier than driving when we moved her from NJ to NC.
We plan on doing two long days of drives (10-12 hours) and covering about 700 miles per day, then taking a nice easy trip on day three. We currently have three carriers between the two: Thena has a small Sherpa carrier, Gail has the same (both cats can easily move and turn in her respective bag), and we have a huge (largest size possible, I think) hard-sided dog kennel. We're trying to decide whether we should keep them in their small soft-sided carriers the whole time, put them both in the kennel, have them alternate between carrier and kennel, or perhaps buy large Sherpa carriers.
Thena is about 11 years old and was rescued as a kitten from a farm. She would like us to think she's regal, but often forgets this and acts silly. She's an affectionate lap kitty and is fairly placid. Gail is about 2.5 years old and was rescued two years ago from a shelter. She is hyper-everything -- hyper-affectionate, hyper-active, too hyper to be a lap kitty because she doesn't have the attention span, and so on. She and Thena get along surprisingly well; we like to say that Gail has brought out Thena's inner kitten. They play chase-me with each other and curl up together on their window-hammock. They do have their little spats, especially since Gail is more energetic than Thena. Thena has ridden in the hard-sided carrier but Gail never has; we've always used her Sherpa bag. Both cats are in good health and up-to-date on their inoculations.
Please comment if you have any suggestions or ideas as to which carrier to use. My worries with the hard-sided carrier is that it's so large that if we have to stop suddenly, the kitty might be thrown. Andy worries that they may get too cramped in the bags (though, come to that, we have had Thena in her bag for more than 14 hours due to an airline nightmare), but he also realizes that most cats like small safe places when they're faced with a major change. Last but not least, I think a larger soft-sided carrier might be good because maybe they won't associate it with their regular carriers, which usually signal a visit to the V-E-T to get s-h-o-t-s. I'll be working on getting them used to car rides without vet visits between now and when we move, but a new bag may help.
We do plan on stopping often and letting them out on their leashes and harnesses, as well as giving them the opportunity to futz about in their litterboxes. Still, even if we stop every two hours or so, it's still a long time for them to be cooped up.