Tows awesome. Haven't gone on long trip yet, but I expect same mileage as my travel trailer. I averaged 9 MPG with travel trailer, depending on wind/terrain. Last year was uphill in headwind, so I got about 7 for 200 miles...
At the end of the day, the 14-15 MPG I'd get with a diesel just doesn't justify the upfront and maintenance expense to me. Even as a daily driver, too wit I average 12-13MPG daily, no dice for a diesel. The gasser is a screamer, but she does a fine job with this unit. If you're looking over the 11-12k mark, go diesel.