I own the Escort Solo S2. It works great, and the best thing is that it is wireless. Runs for a long time on 2 AA batteries. They are on ebay as well as Sharper Image. So easy to quickly swap in into another car if need be.

__________________
2002 X5 4.4i | Black Sapphire Metallic | Premium Pkg | Sport Pkg | Tow Pkg | Xenon | Sliding Load Floor.