Quote Originally Posted by cromoglic View Post
Yeah. An RV would be both fun an convenient, but I think you are right. And we weren't planning an RV trip, we just wanted to find the best mode of transportation for the route we chose.
When it comes right down to it, I suspect that an RV wouldn't be nearly as convenient as you were thinking. In addition to the slower speeds on the highway, there are lots of other things that are time consuming with an RV (hooking up water/electric, draining the tanks, leveling it out, etc) that you might not have accounted for, and based on how you were laying out your trip, I think going another direction seems to be a smart plan.

I suppose that means some of our time estimates will be more accurate, especially when it comes to freeway driving? That would be a relief :-) The car we're looking at is likely to be able to go quite fast. I don't know how heavily speed limits are enforced on US roads (nor how much above one could potentially go). Not that we plan on speeding across the US, but these are things worth factoring in for when we find ourselves with less time than planned.
Well, your travel time estimates will be more accurate, but that doesn't mean they will be accurate. Computer programs still make the assumption that you will be able to drive at or above the speed limit for every minute you are on the road, will never need to slow down for traffic or construction, and will never need to stop for food, fuel, or a restroom.

Typically, it would be pretty rare to be stopped for doing 5 mph over the limit, but if you start doing 10 mph or more over the limit you're asking for trouble (and as a non-resident, you'd likely be expected to pay your fine on the spot). However, even there, if you are driving 75-80 mph on a western freeway, you're still typically only going to average at most 60 mph over the course of a day, once you factor in basic stops.
Edit: another thing off importance is that we'll be able to get a hgher mpg. I don't know hw much exactly, is 15 unrealistic?
It will depend upon exactly what you get for a vehicle, but any modern sedan should get you at least 20-25 mpg, with 30 mpg or more possible with some models.