I don't buy scentlock clothing but I am pretty sure that odor control is important, no matter what one does. Since I started being diligent in eliminating as much scent as I can, my success rate on deer has gone up. I see more deer that don't know I'm there, the deer are closer, they aren't alerted. I hunt with a bow as well as a gun and when I use bowhunting techniques for both seasons, such as scent control, I get more deer per day spent in the field.
Your mileage may vary.