Really ment to give it a 4.75, but I think some comments are getting the default 1.0 rating, bringing down the average.
From my experience. Great product, tachometer is a must have in the Prius. My Before/After FE was 65/68, about a 5% boost for me. Most of this was hitting the right RPM on the Prius.
I've suggested some upgrades to Ron, and most of it has to do with adding a decimal point on some of the values that could use one. Another wish, that is vehicle, not SG based, is a faster polling cycle. Looks to be 500-1000 ms, I can update it from "Normal" but it sounds like that will just cause it to miss it's window and cause even slower updates.
I'm still in the calibration phase, so my accuracy is way out there, but It's getting closer.
For those looking to go beyond the one-size fits all, I was looking at
http://scantool.net . You can pipe the data (wirelessly if you like) to a PC or PDA for logging and realtime analysis.
For what I needed, SGII was a better bargin, but might switch over to a scantool.net solution if I ever get a smart phone that can catch the data. If I do, it will bring a new meaning to "Don't call me, I'm driving".
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