Went to a LBS who has Santa Cruz as a line of bikes.They had a 209 Nomad with Gamut Chain G was nice.But when I went to Gamut and the E-13 web site. On the E-13 site I saw the E-13 DRS dual ring. Are any of you guys running this? How is it? What is the taco guard that the Santa Cruz web is talking about. AKA not being good something about crushing the ISCG tabs. Any info would be great. Thanks.