I bought some lightweight Simms recently and I haven't used my neoprenes since. I fished in my Simms this morning and it was 29 degrees when I started, the water was 38 degrees. I did not get any colder than I do in my neoprenes. I wear Waterworks undrerwaderwear pants with fleece pants over them and a windstopper fleece top over the Waterworks shirt. Keeps me plenty toasty. You have to insulate accordingly to keep warm in lightweight breathables. For my feet I use a pair of the Waterworks booties with polar socks over them. I am, however, an Alaska native so I have a different perception of what "cold weather" really is*JK*.

Justin
CEO, Sauk River Steelhead Ranch