I've been loathing the stock ETC mapping since I bought this car. It seems as though every time I step on the pedal, that all the little 1's and 0's in the ECU go and have a tea party to debate about what instruction they'll pass onto the engine for me.
Previously the Sprintbooster was one of the more common units to augment the ETC map, but I didn't like the fact that it is fixed to their factory calibration. There is a newer one out which has been getting good feedback; it allows 7 levels of "sports" calibrations, an ECO calibration, and it defaults back to normal (unchanged) when you switch off the car.
Info/review:
http://legacygt.com/forums/showthread.php?t=123112
Group buy is running for another FOUR days:
http://legacygt.com/forums/showthread.php?t=123318
Shipping to Australia is extra 20USD on top of the quoted price (basically 170USD). Since our dollar is so kickass (even more than the Vietnamese Dong) it works out to only 185AUD. I have put my name down for one and it should get here by Xmas.