I have the regular model before the Slammer style came out. I bought mine from Suburban Sports. Kewl Cat Peter found someone my size and had him try it on. The Med. was the size i needed, i am 5' 8" , 170#s . I think that if i was 5' 9" it might not fit. The brace showed up and seemed liked it wasn't the type of body Armour i wanted ( i need back surgery), it was too lite. That's because it was the Lite model labeled Reg. I sent it back and had to wait for a replacement from Italy. When it showed up i knew this was "The Goods" ! About twice as strong and thick as the Lite model. It comes with Velcro attached shoulder straps which to me seemed bulky so i removed them. I wear a jacket or t-shirt over it and it keeps it in place. It has a Velcro waist band that it i were to have a beer belly i would have to have to add more to the waist band because it is almost at its end of its adjustment. The Butt protector is also Velcros on and it feels like a huge wrinkle stuck in my boxers so i removed that. If i was a Park Boarder Trash type i would keep it on. I had a blue-white blue-white fall at Summer Camp a few seasons ago and after i stopped drooling on myself i realized that my back came out fine. My neck and other parts of my body hurt. If there were clouds in the sky i would of never know which way was up as i did cart wheels.
When i 1st tried it on it was very stiff ! After a few minutes it feels like a cotton shirt, very kewl. It keeps my back warm like a heating pad and i no longer have to pop pills to ski. Down side it get hot to wear during Race camps and spring skiing is rough. I have not found a way to wick away the heat yet but i am still trying diff. layers. In my case i think the Lite model would not be the way to go.