If you're hell-bent on making car speakers work in your home, at least focus on brands who put actual engineering chops into them. Focal, Morel, Hertz... I don't doubt that they could perform well in a home environment if the correct cabinet were built for them. The crossover work is already done anyway.
Heck, if memory serves, a guy on a forum somewhere was saying that when his old Volvo kicked the bucket he was going to take the 3-way Dynaudios out of the doors and build speakers with them. They were worth more than the car at that point!
But if you believe that $100 pair of Sony XPLOD 6x9's that was thrown together in China for pennies on the dollar is a diamond in the rough, well...