The Apex-i is ~$329. Can set A/F at low and high throttle. A/F is set in 1000 RPM increments and interpolates between set points. High throttle should be tuned on a dyno, but you can (if you are careful) set the low throttle yourself. Do a search and you'll find a webpage by a guy with a DSM that gives a good how-to on setting yourself. Also gives a unit that can display info (RPM, A/F from O2's, etc). Better control than a MAF optimizer, but it costs you.
