One is a "Pro Formance" chip, the other is an "Ultimate Performance" chip. Both for the ETA with the "027" ecu.
$25 shipped
Here's some feedback I found of the Ultimate Performance chip: http://www.e30tech.com/forum/showthread.php?t=98752
$25 shipped
Here's some feedback I found of the Ultimate Performance chip: http://www.e30tech.com/forum/showthread.php?t=98752
