My adventures in tire/wheel replacement is here:
http://greenhybrid.com/discuss/03-hc...14.html?page=1
Here's an upgrade to an 06:
http://greenhybrid.com/discuss/17x7-...82.html?page=1
I'd check with a Honda dealer if you're concerned about fit. As for FE and the spedometer, the diameter of the tire is what you want to watch. Going larger or smaller than stock will affect it. To what degree, I can't say. Maybe others can. There has been LOTS of discussion about weight and how much it matters, if it matters at all. I chose a ground rule that I'd reduce the unsprung weight - did so by 2.7 lbs per wheel. So far I feel good about saying it hasn't hurt FE in any way I can tell. Won't know till the summer (when weather is not a factor) to know if it's any better. In all, I'm thrilled with the new wheels, the better tires, better handling, and a tad quiter ride.