If Street Atlas uses TIGER data, then I can say for sure that it's not all that great. My street for example suffers from road drift in that it thinks my road turns when in fact it doesn't. There is one road in particular which is also straight, but on the map it performs a quick z turn. Everything to the west of that point is shifted about a 1/4 mile.

It would be useful if using it to print out maps, or just interstate travel, but when you actually use a GPS you find that it's lacking.