My 2008 FEH FWD came with 2 options: "side steps" and "engine block heater". I have also put in the black rubber mats and the rear cargo shade. Can't say whether this affects MPG and as I didn't install them I can't speak to whether there are any issues related to installing these on a FEH. My wife and mother-in-law are both shorter women and it does help them get in and avoid some of the mud and snow. I find it handy for knocking mud and snow off before I get in.
Am considering adding some mud flaps and maybe a bug deflector. Would be interested in anybody's feedback on these two options also.
Thanks,
Bruce | 
