I sprained my left MCL after falling down in a funny way, requiring crutches, a few trips to the doctors office, and weeks of heat and cold packs to control the swelling. Initially I used a fairly good neoprene type velcro wrap knee support (for twice the price of the Shock Doctor), which worked very well to keep my knee compressed, but the neoprene got very hot very fast, and my knee wound up being wet from sweat all day. The wrap was also too tight to allow any normal walking, and wearing it to the office became more of a hassle than it was worth. I ordered the Shock Doctor Ultra Knee Support with Bilateral Hinges to see if it would be any better for wearing all day. It was better in almost every possible way. Comfort: Not only is this knee support much more comfortable than the neoprene wrap type support, but it feels so good when you first start wearing it the other knee gets jealous. I will probably continue to wear this every so often now that my MCL is mostly healed, because it just feels great to have such great knee support. Heat Retention: There is really almost no sweating issue at all with the Shock Doctor, due to the meshed cushion design. Airflow is very good. Except for the hottest of days, my knee stayed relatively dry while wearing this support. Compression: While not as firm as the neoprene type, the padding is thick and soft, giving quite a lot of support. My knee always feels great with this on. The neoprene is just too tight to wear every day if you plan on walking around. Odor: While the neoprene supports obviously come with the somewhat gross neoprene/wetsuit smell, they also get stinky from the constant sweat they are in contact with, which just makes the neoprene stink even grosser. The Shock Doctor support has very little detectable odor at all, and it mostly stays that way even after extended use. Effectiveness: The first two weeks after my MCL sprain required a very tight support, which the neoprene does better. If you just hurt your knee and need a very tight fit, maybe go with the neoprene first, but keep in mind it is more difficult to walk in. Of course, if you just hurt your knee, you probably aren't in the mood for a lot of walking so it may not be a problem. Once you start going back into the real world and need to be mobile, the Shock Doctor is the way to go for sure. I do not think I would have recovered from my injury had I not worn this product for a few months after getting hurt. Sometimes my knee starts to hurt again after a few days or weeks of not wearing the Shock Doctor, but that goes away the minute I put it back on. Size: While very bulky looking, I can still wear this under a pair of Levi 501 jeans without any noticeable bulges. Not as low profile as the neoprene supports, but not too big to fit under a pant leg. I actually prefer the extra bulk on this item, as my knee is safer from external impact, something you really don't want while your knee is healing. Sizing: As you read the reviews for the Shock Doctor knee supports, you will see a lot of people confused about what size they should get. I ordered the X-Large, even though I would not consider my legs larger in diameter than 'average'. I am 5'10' with a heavy build, but again my knee does not seem to me to be "large" and certainly not "extra large", but the X-Large fits perfect. If in doubt, and you really need knee support right away, I would recommend ordering two sizes, and returning one you don't want to keep back to Amazon. When your knee is injured you want to support it as soon as possible, so messing around with measuring your leg and calf and using a sizing calculator may not be at the top of your worry list. Construction: Construction and design of the Shock Doctor is amazing when compared to its competition. It looks and feels like something a professional athlete or soldier would wear when they needed knee support to keep moving. However, there is one design flaw, and to me it's sort of a big one, which is why I could not give this product the five stars I really wanted to give it. The buckles that the velcro straps go through, which take a lot of pressure while you are tightening the straps, are made of plastic. This was not a problem at the beginning, but after a few weeks of every day use, the top buckle cracked and broke while I was adjusting a strap, rendering the entire knee support useless. Amazon cross shipped me a replacement right away (thanks again, Amazon) and I was back in business in two days, but now I am very careful about not pulling the straps too hard. Of course, a tight fit is what you want from this product, so this is a pretty big design flaw. However, it is not bad enough to avoid this product, as it excels in so many other areas. If Shock Doctor started using metal buckles instead of plastic, this item would easily be five stars. All things considered, this is one of the best products I have ordered on Amazon.