What is this "too cold" point you speak of? I hit the same temps as Sixty Fiver and didn't really have an issue. I won't say that I was really super warm, but I didn't lose a finger or toe either. With chemical enhancement [handwarmers and whatnot], I could stay out in those conditions for quite some time, as long as I didn't have a mechanical and I kept moving. My biggest issue is always my hands and feet. My core, arms and legs are always good.