I have done 15-20+ rep SLDL but as a main back exercise, not as a finisher. If the hand grip is changed to extra wide (collar to collar), from time to time, a better stretch and feel to the movement is achieved. Have also done shrugs at the top position of some higher rep SLDL's, with that extra wide grip. Pretty affective on the Ham's also when done with a fairly straight back. Improves the over all regular DL when I go back to it. Good Luck.