I think it depends on how many groceries and how far you're going. I am single so don't buy much and the furthest grocery stores I ride to are 2 miles away. In my backpack I can get a gallon of milk, a whole chicken, and some other stuff in there no problem. Sometimes I stick some gel freezer packs in there and get ice cream. I prefer to lock my bike in a heavily travelled area, typically to the big metal rails right by the store entrance. On the other hand, if you are planning on big panniers to carry a ton of stuff, maybe the CAAD10 is not as great a choice. I always enjoy commuting on my CAAD9, but that's just me...