The comments about SA 2008 are right on the money..... that version has some problems and annoyances, but I just ordered the 2009+ and LT40 bundle a few minutes ago. As soon as I load it and test it, I will try to get back here and post my opinion and findings. I have used DeLorme Street Atlas for a number of years (like since its beginning), and have generally liked their stuff, but 2008 had a few too many errors and oddities for my liking.
On my October, 2007 trip (to/from Myrtle Beach, SC), I ran the laptop with SA2008+, a Garmin GPS Map 76CSx, and the factory-installed in-dash (Alpine) unit on my Jeep for comparison. The in-dash unit had the least functionality, while the Garmin and the DeLorme each had their annoyances and errors. Maybe this new DeLorme setup will be a real improvement.