B,
I've used the R1(hoody) for many years over a cap1 or cap2 from temps of +45 to -25 *F. I've never tried the R2, but have an R3 that sees mostly 'casual' use though I will say that the warmth and breathability are outstanding. The nice thing about the R1 hoody is how fast it dries. The hood fits very well under a hat or climbing helmet, and it has thumb loops that help hold in the warmth and keeps the sleeves from riding up your arms. Just a kick-ass fleece all the way around.
