I'm in the market for a new backpack as I've put my Baltoro 65 through the wringer and I'll be hiking the JMT this summer. I figured it's time to finally break into the UL backpack game, so I've spent an embarrassing amount of time researching backpacks. Unfortunately, since the the Small Kakwa 55 is sold out for months, I've narrowed my search down to the ULA Circuit. As I'm sure many of you know (or maybe I'm just a UL gear nerd now), the ULA Circuit has several fabric options. I'm particularly interested in either the standard robic material or the new ultra material.

I am in good shape and am not worried about weight difference between the two fabric options. My main concern is waterproofness and whether or not it's worth it to shell out more money for the ULA Circuit Ultra which is waterproof (not seam taped). In the Sierras and PNW, it's not uncommon to be hiking in rain for a few hours at a time.

With whatever material I pick, I will be packing my sleeping bag into a liner. Then, I'll stuff my clothes (puffy jacket) around my bear canister. I'd prefer not to use a rain cover since it's a piece of gear I wouldn't get consistent use out of in the grand scheme of a thru-hike.

Does anyone have experience backpacking with the ULA Circuit (robic) without a rain cover? How did the pack do? From what I've read, it will get waterlogged under intense rain that lasts longer than 15 minutes or so. Did moisture seep into the bag?

Thanks in advance for your knowledge and experience!