Started the FP regime in the Maxima 435 miles ago. Without any real deviation in my driving habits/routes, I am averaging about 1.7 more MPG. I have backed up the in-car fuel computer against my Harrison/Palm datalogger and the results are the same. 93 octane goes in as per the manual recommendation for full performance potential. I get fuel at the same station and enviromental conditions around here have been fairly consistent. I've done a baseline ignition timing log since the car was new 4763 miles ago. I thought maybe it was finally over the "break-in" hump but it started the MPG climb almost as soon as the FP went in. I will drop to 89 and check to see if the timing retards any, if not, then down to 87 for another check. Bottom line, this stuff seems to work as advertised and verifies the good reports from others on this board. I like it