We're on the road in a Class A with two cats. We have large cages for them when the road is rough, but for the most part, they stay on the bed. If in the cages, we've learned which cry means "I gotta peeee!" and take care of it as soon as possible.
When we stop for lunch, they get lunch and water, too. Then we make sure they pee before they're caged. Makes for a longer lunch stop, but with elderly cats, that pee break is a must.
When we play the radio, it has to be country music, preferably all males singing, or one of the cats complains. The other could care less - he even likes my singing, and I'm a soprano. He's also 19 1/2 years old, so he probably doesn't really hear me that well...
All that said, you have to be attuned to each cat's personality and work with it, but they'll travel just fine in the long run.