Just bought my HHR a couple days ago and so far I'm really enjoying it. I went with a pretty stripped-down model, but the difference in features wasn't worth the extra money. I would recommend the 5-speed over the automatic, the ride is a lot better and it's really a lot more fun. If you can afford a little more the SS model is awesome, but I didn't feel it was worth 8k more then the basic LS model that I purchased. It's a very smooth ride for a smaller car, handles nicely on the freeway and driving through town, plus they unique style gets a lot of looks and compliments.
Gas mileage. I've been driving around for two days and the gauge hasn't moved. Sporty looks, even without all the extra features.
The cup holders are in a very awkward location and there are only three of them. The definitely get in the way of the emergency brake in the 5-speed. The front window also takes a little time to get used to. It's very low and difficult to see traffic lights, especially for someone over six foot.