I should say that this is my first harness, and I have exclusively been using the harnesses that they lend out for free at the climbing gym I belong to...the noticeable difference I experienced on my first climb was amazing! this harness is super lightweight, but also very sturdy and secure - and so so comfy in the legs and around the waist! I love the adjustable leg straps (I originally bought the Sama but returned it because the fit in the legs wasn't right for me). there are plenty of gear loops (although I don't have any gear, yet), so this harness should be very versatile and adaptable as I grow as a climber.
I purchased the medium and it fits great - I am 6'1" and 188lbs - waist 34"