I agree that a lot of the interstates are marked at too low a speed. I live in Columbus, OH and I-70 is one of the straightest, flattest highways around. It's speed limit could be raised to 70 or 75 safely, but currently it is set at 65 for cars and 55 for trucks. The state decided that the money it got from fining truckers was worth losing fedral highway funding (the fed tried to push Ohio to raise the truck speed limit to 65). That's just evil.

On the other hand, have you ever driven I-79 through West Virginia? It's speed limit is 70, and I think that it is too fast for portions of the highway. It is very windy with some steep inclines, and I've seen some near accidents there.

Also, 25 for neighborhoods is very very reasonable. I know it seems slow, but that is pretty much the max speed you can be traveling and expect to stop if a child runs out from in front of a parked car. I live on a very wide street, and it seems like everybody does at least 35 down the road. They treat it like it's a drag strip, and there are many children that I fear one day will be hit by a car. I've had my share of balls roll out in front of my car, and I could stop, because usually I drive UNDER the speed limit of 25 on my street. I doubt some of the riceboy cars that race up and down the road could do the same.