I have a seatpost rack and trunk bag I got from Performance Bicycle that I use on my road bike on occassions when I need to bring a change of clothes. It works well and I don't notice the weight nor does it affect handling. I also believe that the Axiom streamliner rack which you nixed would work very well for heavier loads. I don't know what reviews you read but I would not hesitate to hang a couple of small panniers off that rack for commuting purposes. I mean your intent is not loaded touring, right?