I have an older version of the Dealertool, it has been a great help for general maintenance. It gives vaccum pressure readings for throttle body adjustments, has many system check procedures, and can read and clear ECU fault codes. The newer versions aid in bleeding the ABS brake systems, (my '08 is non ABS). The Dealertool can not alter the ECU tunes for that you need the Tuneboy or TuneECU software.
The Tuneboy has been around longer but is a bit costly. TuneECU is similar to Tuneboy but the software is free and all you need to buy is the proper cable to connect the ECU to a computer. From what I have read on this forum the TuneECU may lack some of the graphics and fancy features of the Tuneboy but the price is right and it is worth a try. Just be careful if you start altering the tunes, you can do some engine damage and the mistakes will be costly.
I have the software and will do a search for the proper cable info. My Tiger is running great but am curious to see what this TuneECU can do, if I can get through the software and driver set ups