This harness/hiking pack is exactly what I wanted. It's the perfect size for the less lengthy hikes my dog and I take. I can fit exactly what I need in the pockets and the fit is great. My dog is 85lbs and lanky...she's a lab/Rott mix so she's big in the torso but skinny everywhere else :-) We have the XL and it's a great fit with room for her to grow, should that happen. We've taken a few walks with it in some pretty warm temps and she doesn't seem to sweat too much. After several weeks of using it every day, I noticed she had shed a lot but the material doesn't smell yet, which is something I noticed with her harness from another company. We're excited to get a lot of use out of this during the summer!