My new SG A-53T chainring didn't come "ramped and pinned". I think this means the teeth aren't cut and beveled and there aren't any pins to aid in shifting. It's a beautiful chainring with a much nicer finish than the stock one it replaced. I bought it from my local and knowledgeable LBS to work on a full ultegra 53/39 double setup. Will I be giving up better shifting for better appearance? What are the differences in the various versions? No, it's not Biopace.

55/Rad

yes, you will be giving up performance. those ramps and pins are what grab the chain and bring it up to the next chainring. otherwise, you are just sort of shoving the chain over onto the next ring, and hoping it catches.