Hi there, LHG sell 2 types of Jackets. The colour determines the material finish. One is straight sil/Nylon says some breathability, a wee bit lighter, the other which I have is the Sil/PU. Mine is absolutely NON breathable and a bit heavier 195gms in M and Espresso colour.I have wetted it out on the inside several times-BUT it has been very slight, a sheen of very light condensation. I was dry against my skin wearing light woolen shirt under a Thermal Patagonia Hoodie. It is the R1 light I think of it as. Sweat wicked to outer surface and for 2 hours in consistent rain 5-6 C, I was bone dryon the skin. PS pit zips fully open the whole time-No water came in through them AT ALL. I think this is the beauty of the LHG pitzips -large enough to vent some heat but not too big so you worry about water ingress.
PPS. The outer surface of the jacket NEVER wetted out, thus I stayed perfectly warm/comfortable on the inside. PPPS as there is no elastic around the bottom hem this is also a venting point. All the best.