pump gas engine vs. high compression

In the interst of affordibility, durability, conveinience, go with the pump gas motor. You COULD run high compression on E-85 but thatmay be an issue of availibilty in your area. High Compression engines will require usually somewhere around 108+ octane & at $8.00/gal at least filling up the tank, even for a week-end cruise gets pricey. Plus you have the issue of even findint THAT kind of fuel.
Today's technology let's you run as high as 11:1 on premium unleaded so I seriously doubt you'll miss having an extra point or two in compression.