Thanks for your insight. I'm at the 15ish lb mark now but hope to drop another 5lbs by this summer once I upgrade my sleeping bag, pad, bivy & tarp (wasn't kidding about the complete overhaul). It seems that the Ohm would cover this fine but I'm also the default pack mule for the family and have other interests (e.g. fishing, photography, etc.) which will substantially raise my base weight from time to time.
I also have a long-term goal to through hike the JMT and PCT so having a pack which is bear canister friendly is a plus too.
As you mentioned, the volume is close enough between the two that I have a hard time justifying owning both. All things considered I'm going to pull the trigger on the Circuit and learn to live with the 10oz penalty. It only took me four months to make this choice!
Thanks again Sumi!