4.56s on the steet ?

Again, before you spend any money, all you have to do is drive the entire 40 mile trip everyday in low gear. Don't shift. It's a free test to see if you'll like low gears!
Do it for a week. Try it down the highway for that "twice a month" it'll be used there. If you can live with the engine taching like that, you'll love 456s because that's what the drive gear will feel like all the time.