True, tracks need to be kept clean and lubricated- on both types of doors. Sliding, overhead hung doors that have the tracks cleaned and lubricated annually are no more difficult to open now than they were when we installed them 15 years ago. And they are heavy, solid wood doors- we hung them with the help of the tractor bucket.
however, the new tall RV doors with windows are bright and cheery, open by remote control, and if I were building again I would put them in. My barn does have very tall ceilings, so, the tracks that come inside the building would not be a head room issue except if a horse really reared up- the tracks hang about 6 inches down from the ceiling. In our old car garage this was a problem, since the tracks were at 6 1/2 feet in a 7 foot garage and our taller friends were forever walking into them, so we got rid of them and put in swinging doors instead.