There was a time between 2003 and up until around 2014, the Army had little interest in regulating the specific type of common bootwear. This led to companies using mostly synthetic materials to make THE most comfortable boots I, and many others, have ever worn. No break in, no marks, no rubbing, nothing. Since 2014 though, synthetics were disallowed and boots started to suck again. These Light Assault Boots, while not quite the same, are definitely reminiscent of the synthetic material days!!! Super light, barely any break in, no pain or cramping .... They feel like a running shoe! The downside is their reputation for durability. While it really depends how one treats their boots, i'm sure not using 100% natural skin makes for a less durable product by comparison. Still, it's a compromise I am willing to make since I can no longer wear regular boots anymore. I'm totally sold!