I was speaking more in terms of real world milage - the VW TDI isn't rated 50 highway either - but my brother in law has gotten that good of milage more than just a couple times on road trips.
Heck, my audi is rated 23 city yet I've been averaging 30mpg with 80% city driving and with a very very heavy foot (since it's a lease).

Yep, I've heard E85 has less potential energy per gallon, but I'm sure that will equalize with cost savings if oil prices get any higher. Plus, I'd rather pay a small premium to domestic farmers if that's what it takes. I wonder if prices will drop as the infrastructure for E85 increases (if it ever does) and economies of scale kick in to our advantage?

BTW I thought I also heard that E85 allows for a much higher compression ratio before predetonation becomes an issue. So in other words I'd think that E85 would be 'premium' octane (plus some - heck, plus a lot) be default. Considering I fill up with premium in my Audi anyway - assuming the E85 vehicle was designed to take advantage of the E85 CR stability and setup with a higher CR and advanced spark timing and whatnot - I'd think E85's price should be compared with premium octane fuel. (assuming what I've recall is correct)

 

Mercedes discontinued U.S. sales of the E300 diesel after 1999 and the E320 CDI was introduced to the U.S. in 2004 - though it had been on sale in Europe since 1997.

 

Yes, E85 does allow higher compression ratios. Octane equivalency puts it over 100 compared to gasoline.