My 105 shifters (5600?) are apparently the last ones before under-the-bar-tape. Good news, less friction, but the RD shift cable eventually breaks in the shifter. With a bright light, reading glasses, a pick, fine needle nosed pliers and 4 hands I can get the nub out. 7,000 miles seems to be the magic number. I’m probably getting close to that now, need to check it again.