Love my HHR and I won't give it up, but I hate that it has been in the shop so much. It is a blast to drive - especially since mine has the 2.2 with a 5-speed transmission. Great fuel mileage - average 27 mpg daily driving and 33 mpg on highway. Items replaced thus far, upper and lower steering shafts, front brake rotors and brake pads, radio (three times), front sway bar bushings, and body control module (related to radio issues). Running boards and Splash guards are a must if you experience winter driving conditions (protects paint on rear doors). Changed tires to Goodyear TripleTreads (Original Firestone Affinity tires were junk) and I now have better control, handling, and traction.
Great retro body styling of vehicle. Total blast to drive consider the 5- speed transmission. Room for the whole family - including the dog (golden retriever). Location of oil filter element (front right side on top of engine). Large side mirrors (compensates for the poor rear window visibilty.
Relocation of window controls to doors - corrected on 2009 model. Make running boards and splash guard standard equipment on all models. Use different tires - oem tires are terrible in winter and rainy conditions. Add key entry to rear hatch and ability to open glass rather than the whole hatch.