I had 520 miles on my 09 HHR when we left on a trip to Denver NC via Norton VA. It was pretty well loaded down with luggage etc. Lots of steep hills to get to Norton but it pulled them very well. no problems with the brakes either except the pedal does feel soft. Coming back to Ohio thru the Blue Ridge on I77 it ran great with the cruise set at 70. For the trip I averaged 29.2 mpg and it was a comfortable ride. You do have to know how to set and use the outside mirrors as there are blind spots.
I love the body style and the cargo room.
Put a coast or cancel button on the cruise so you don't have to keep tapping the brake pedal to disengage it.