F150 EB vs 5.0 towing

I have been researching the EB for a while and it seems the mileage does vary unloaded (seen anywhere from 12-16 in town and 16-22 on the road, again unloaded). The 5.0 on the other hand gets 1-2 mpg less on average; I haven't seen much variation with unloaded 5.0 owners. Since Ford is running a huge rebate with the 5.0, is that worth several grand for a similarly equipped EB? Unless something unforeseen happens, I might tow once a year maybe twice so the dealer said I have until the end of the month. I'm not in a big hurry, so I'll ponder a bit more. :-)

Thanks again. It's giving me something to chew on.