The verdict so far: no consensus. With input from Audiogon and other research, my impression is that aftermarket jumpers range in price from a few dollars (DYI) to many dollars (e.g., AudioQuest or solid silver). What may shine through the diverse comments is that in some systems, there may be some change, which some who experience the change say is a good change. So, no consensus and a caveate: your experience may vary from that of proponents and naysayers, based on your system and preferences. I appreciate all the responses which have helped me think through taking the leap into after-market jumpers, and how much moolah I want to invest.