I bought a pair of these coveralls primarily for use in my shop when I am welding. At 6'2", I ordered 46L just so I would have ample length in the legs to fit over work boots - there is nothing worse than a hot spark that finds it way into your boot while in the middle of a critical weld. The 46L is a bit long in the sleeve and the legs, but for my use, the fit is perfect (even when squatting or sitting there is still ample coverage over ankle).Out of the box, the flame resistant chemical treatment is obvious with a fairly strong smell. That went away with a quick wash in cold water, mild soap, and air dry on a hanger in the shop for a day. I've had them for a couple of weeks now, and wear them for a 2-3 hours daily. I've had several hours each day at the welder or grinder station with continuous hot metal sparks and spray coming in all directions, and the flame resistant properties are exactly as advertised. I see no signs of burn through. The welder puts out an intense amount of UV rays from the arc. Many cheaper (lighter) materials will let enough of the UV through that arc sunburn is common through many materials. With nothing but lightweight long sleeve and long leg underwear, I've not experienced any arc sunburn through the 9 oz material. Shop temperature varies from 50-70 degrees F. At the lower temperatures, these are just the right weight. However, when it warms up in the shop (70-72 F), I feel the heat - these do not breath, so air circulation is minimal (but if they did breath there would likely be UV leakage from the arc - so I tolerate the warmth in favor of UV protection)For the purposes that I use them, these are perfect; I can find nothing to complain about yet. Zippers and snaps appear to be decent materials. Sewing at seams is double thread in some places, single thread in others. I would have preferred double thread seams everywhere for durability in shop wear, but I see nothing to suggest these will fail in normal wear in shop environment.At $60 pair, they are more expensive than many others. BUT - the protection from UV and flying sparks and weld splatter is most important to me, and these Bulwark coveralls are exactly what I wanted and needed. I'll buy another pair soon (these will need a second washing soon and I don't want to be without them for the day or so that will take)