Fizzer

I've seen people make longer trips than that on DOT slicks, but it may or may not be a great idea depending on your route, situation, and risk tolerance.

As you said, dry warm weather is of course a must. Also keep in mind though that Hoosiers are much less robust than street tires. Debris that a street tire would shrug off could cause a puncture on an R6. They're made that way on purpose to be as light as possible.

Other things to consider: need to run higher cold pressure than you would at the track. You'll pick up and spit out all kinds of dirt and rocks that street tires wouldn't. Lower traction on any kind of dirt / gravel patches.

Baisically, if you're super careful and the roads are in good condition with no threat of rain, you should be ok.

Here's Hoosier's take on it (cover their butts for liability): NOT FOR HIGHWAY USE: All Hoosier Racing Tires including DOT labeled Hoosier Racing Tires are designed for racing purposes only on specified racing surfaces and are not to be operated on public roadways. DOT labeled Hoosier Racing Tires meet Department Of Transportation requirements for marking and performance only and are NOT INTENDED FOR HIGHWAY USE. It is unsafe to operate any Hoosier Racing Tire including DOT tires on public roads. The prohibited use of Hoosier Racing Tires on public roadways may result in loss of traction, unexpected loss of vehicle control, or sudden loss of tire pressure, resulting in a vehicle crash and SERIOUS PERSONAL INJURY OR DEATH. Exception-"PRO STREET"

Also read this: http://www.tirerack.com/images/pdf/warranty/HOOSIER.pdf