Seriously, if your vehicle is OBDII, don't waste your time looking for anything beyond the best price on the Scanguage II. It's functionality far exceeds those other options and at $150 or so would be difficult to replicate for the money.
My current tank is looking good - I have to hold off the temptation of topping it up to see how I'm doing, but it is beyond anything I've done before!
__________________ Team GasMisers5 - #1 for first three rounds of the original GS Fuel Economy Challenge
Miles displaced by e-bike since 1 Jan 2008: 62.6 (0 kWh used)
Hypomiler
Just remember that whatever the gauge says, the test is at the pump. My car came from the factory with an instant and average fuel economy feature and it always reads several MPG lower than what I get at the pump.