I just got the Peloton 200s in the mail 2 days ago. Tried them on immediately, like everything else, including under the Alpine pant that came with it. I already own the merino 145 zip ons.
Can't make an accurate call on fit because the merino 145s are a size med and the P200s a large. I sized up on the P200s specifically because I expect to start with the merino and add the fleece if/when needed and figured they'd just go on over the merino. However, the P200 fits really comfortably on its own. I can easily wear either size and be happy and not wishing for the other. But I like how the size large doesn't constrict my legs. In the merino, I find I need to stretch them a bit to get the zippers started and not grab hair when I'm zipping them up. Don't need to do that with the peloton's. Waist and length are good; I don't find the large too long nor do they want to fall off my ass. To keep things in context, I'm 175lbs with a 32" waist and a 30"/31" inseam. I think I'm gonna find these really good as a part of a layering system. With the lightweight merino and alpine pant plus a rain shell, I pretty much have all conditions covered other than ND/WI/Arctic, none of which I hunt in.