My son just finished a lease on a Colorado and he had no problem with the truck, last week he bought a new 2010 Canyon with the 5 cylinder and the off road package, I would think you should be able to nurse 30 MPG on the highway if your foots not too heavy,the truck has a 5,500 tow rating with 240 HP and 240 ft/lbs of torque so it should tow small to midsize boats with out any trouble at all.
GM has some nice incentives on their trucks now if memory serves I think the truck was 25K.
It`s a nice looking truck and rides pretty good as well.