For most roads, length has relatively little effect on things. It does matter a lot more when parking or maneuvering in tight quarters (gas stations, tight parking lots, that sort of thing). With my 32' class C, I find I am more concerned about height and the comfort of driving over bad roads than I am about width and length. I would not care to drive it through a major city center, though, if I could avoid it—even if I knew I had parking available wherever I was going. The width does come into play sometimes with the comfort level of driving through construction zones, particularly when they bring out the Jersey barriers at what sure looks to be the width of the RV plus an inch on either side (though that is an illusion), and doubly so at night when it's harder to gauge how close one is to them in the mirrors.
The big picture window in front of a class A sure is nice until you drive into the sun...then the overhang of the cabover is really nice. Frankly, for one person, it's rare to really be able to catch much more than a passing glance at the scenery while driving.
