I've worn alot of shoes over the years, my favorite hands down was the Moccasym. I believe this is my new favorite shoe i will use as my go to shoe. Personally i am not a huge fan of the overly aggressive down-turned shoes but for lack of a better word i do like a "medium" aggressive shoe and i feel like the Quantum is just right. I ordered 1.5 sizes up from my street shoe(10.5 to a 12.0) and they were a perfect fit, a little snug and with just a hair of stretch they'll be perfect. I dont have the widest foot but i dont have a narrow foot either so i'd say for most people whos feet are just a little wider than normal 1.5 sizes up is a good start. these things are already comfortable and they arent broken in yet. Its aggressive enough to get on very small edges and on small slick sloped holds, but not overly aggressive that you cant smear properly or feel the urge to yank them off half way through a climb, you'd swear you had a huge foot hold underneath you on some of the shakiest holds.. these things seems to expand and contact every available centimeter. Overall everything seems real solid, the laces are strong and you can really cinch these puppies down without fear of busting through an eyelet. The inside is not extremely minimalist like some of the Sportiva models, its got what i'd call a thin layer of padding but its perfect, i can still feel EVERYTHING. When you get them you'll notice a pretty substantial down hook on the toe, that thing grabs like a monkey hand. After several climbs i was very impressed with this shoe, i'll be buying them until they discontinue them for sure. i want to say its an all-around shoe but that seems to take something away from how sweet these things are when doing anything technical, its an all-around shoe without the all-around shoe look/performance. so far its been dead on for bouldering and technical climbing. no cracks yet but its got the rubber on the toe for it, though, you might have to size them differently for all day crack climbing.. Oh, and these things look sick to boot. get these!