I owned a 19' and now a 25'. The 25' has far nicer road manners. I think the real reason that it does is because its heavier and has two axles. When the fresh tank is full, it's also right above the axle on the 25. On our 19 it was under the front streetside dinette seat.
A good hitch will help minimize any dog effects, but it may not solve some of the hopping I saw with our 19', though I will admit, the hopping was very minimal.
Computers manufactured by companies such as IBM, Compaq and millions of others are by far the most popular with about 70 million machines in use worldwide. Macintosh fans note that cockroaches are far more numerous than humans and that numbers alone do not denote a higher life form. -NY Times 11/91