Just read an interesting article by a company with a good reputation about comparing their efi models to the carb models. I thought it was very interesting. Its not that the efi saves approximately 20% in fuel and would take about 2 years to pay for the additional cost at 800 hrs a year that surprised me most. It is the fact that carb or efi, the larger engines used less fuel than the smaller one. Which leads me to believe that having more power works the engine less and doesn't necessarily mean the fuel economy will suffer. I realize this is just a comparison of 4 engines by one company but it's still interesting. I like efi but I still think it takes too long to pay for the extra cost and if you have a repair out of warranty it may never pay for the additional cost. Heres the chart based on saving at 800 hrs per year. If everything goes well you will put some money in your pocket but if if the efi needs out of warranty repair you could end up in the red. I'm an efi fan but still think it cost too much as an option on "most" ZTR's. Of course it's all just a matter of time till we are all running efi (due to the epa) and that may not be a bad thing.