I bought these for more substantial protection while mountain biking after sustaining a broken hip in a road bike crash where I wasn't wearing armor (Who wears armor on a road bike?). I am 6'1', 180 lbs, 34" waist and had a comfortable fit with the extra large. They seem breathable, but I haven't worn them in the summer heat yet.Three months into my recovery I wore these on a mountain bike ride and, sure enough, crashed and landed on the same hip. Bad news was that I needed another surgery. Good news, I think these shorts may have prevented it from being worse. There was a pin running diagonally threw my upper femur ("hip bone") that intersected a longer (16") pin that ran through the middle of the femur. The blow from the fall hit just right to drive the diagonal pin through the rest of the bone and into the pelvis. It was just barely enough to require surgery to replace that pin. BUT there was no bone break or fracture. Did these shorts make the difference? Impossible to say for certain but rest assured I will not be mountain biking without them in the future. They seem to move well while riding and I don't feel restricted. I am a serious recreational mountain biker so I don't know what a hard core racer might think, but I like these enough that I bought a second pair. I recommend make sure they are worn high enough on the hip to insure they protect where they are supposed to. (Don't wear them low.)These have worked grate to protect my hip bones from impacts. After two large bone bruises to the same spot on my hip, I started wearing these. After I started wearing these I had about 2 more impacts to the same spot and didn't feel a thing. These work exceptionally well for large impacts to certain parts of the hips.Pros:1.) Really grate protection on the occasion an impact lines up with the hard shell protection provided by this product.2.) They appear to hold up well in the wash.3.) Breathable mesh.Cons:1.) Small, and doesn't come in large sizes for larger adults. You'll have to modify them or have them modified by some one in some way if your a larger sized adult. They have some strange material around the bottom (close to the knees) that is a bit uncomfortable and sweaty in hot weather. This material looks shinny like some kind of plastic or latex something.2.) Takes a day to air dry, which means your out at least one whole day waiting for them to dry after washing.3.) Its a bit embarrassing from a fashion sense (something I'm willing to give up for being able to continue riding after a large impact).These would be okay but I sent back due to not enough hip protection. The thigh is stellar but anything in the hip or waist or gonna turn out BAD ... and I have had an accident where I got a bad blow on that area and I refuse to run anything that doesn't give me full protection. For Offroad MX no go ... but for lighter duty like mountain biking etc. they would be fine.Buy one size larger than you normally wear. I've had these for years, and finally put them to the test today in a nasty dirtbike crash. Bruised hip bone, but no broken bones or internal organ damage. I can only imagine how bad it would have been without wearing these shorts. Also recommend wearing dirtbike pants with foam hip pads for extra protection. The tailbone pad gets a bit uncomfortable if you're sitting for a while, but worth it for the protection. I'll continue wearing these shorts after how they performed today.UPDATE: I bought a pair of Bohn armored shorts and now I'd recommend the Bohn shorts over the Alpinestars. The Bohn shorts have excellent hip armor where these only have some soft padding on the hips. Plus the Bohn shorts are much more comfortable.I'm 6'1", 190 lbs., my jeans are roughly 32x32, and I always wear size medium with shorts, trunks, sweatpants etc. Other reviews have said to size up, I'd recommend the same. I ordered the large, and it fits perfectly around my waist (maybe a little too tight around my legs, but keep in mind my legs are a lot thicker than most people my waist size).Apart from the sizing, the product itself is extremely high quality. It does it's job. I feel very protected and comfortable.I got one size up from recommended because i didn't want it to be too tight after wash. item has been used and washed several times and still holds it together. I think if i got my actual size it would have been a tad bit tight, what i selected(XXL) was perfect. the padding is solid and has saved my tailbone from some serious brushing. I would defiantly buy again.Got these through Huck n' Roll. Delivered on time.These are some slick duds & I found the fit to be just right. While probably not the best shorts for long pedaling sessions they are the ducks-guts for downhill bombing. After awhile I didnt even feel them under my riding shorts. I've yet too try their protective quality in a big endo get-off but its good to know they are there for the inevitable.Riding a KTM "Ratchet"DingofishAs a new motorcycle rider and a strong believer in ATGATT, I decided to buy this. I wear this under my jeans along with knee and ankle guards that I bought separately. I am waist 34 with big legs and it fits me fine. With plastic and stuff, I would probably hand wash it and hang to dry.Edit: Been buying so many things lately, I forgot this was not a one size fits all...I bought a size L.No incomoda para nada a la hora de pedalear, tanto que incluso valen para enduro con un boxer con badana debajo, ofreciendo la maxima proteccion cuando se baja a velocidad. muy contentoExcelente productoOttima protezioneLo q esperabaLe short est très bien aéré ce qui évite la surchauffeLes protections sont de très bonne qualitéLes plaques rigides peuvent gêner lorsque l’on enjambe la selle en motocross surtout si on est petit