I recently purchased the Infiltrator jacket (along with the pants). A couple days after arrival, I had the opportunity to put it to the test. 5 hours in the rain, 42 degree weather and in full kit. I was quickly sold on the quality. I am 5'10" 190Ibs and the large fit perfectly. It was form fitting enough to comfortably be under kit but not too tight for layers underneath. The stretchy material in all the right places makes this system feel one with your body. The hood works great with or without helmet because of the straw string system. I had buyers remorse for a short time until I realized what a game changer this jacket is.