I've been looking to cut the weight of my current rain shell from 15.5 ounces down to at least 12. This is not just about weight cutting, but about breathability – I can do much better on breathability than the material used in my old Patagonia hardshell (love Patagonia soft shell jackets, but I find their proprietary hardshells not very breathable). The OR Celestial is a fantastically well-designed jacket made of Paclite – like everything about it except that the side torso vents don't go up very high – I thought they'd make it to the armpit but the zippers don't even come close. Well designed hood, good length front and back, room for layering, etc.
The Montbell Peak offers pit zips for only another 2 ounces – if the length is good (meaning good coverage front and drop back – I like longer hard shells because I'll often hike in rain without rainpants) it might work better for me. I can produce serious heat when moving and I can't imagine using a hardshell (even eVent) without pit zips. I've heard from Benjamin Tang and others that the Montbell Peak material is very breathable. It's only the length I'm concerned about – it's hard to tell from Montbell's website.
I'd really appreciate any thoughts, particularly form someone who may have seen them side by side or tried both on. If I have to, I'll just order a Peak Jacket and try side by side. No stores near me carry either.

