I'll be taking a Tenkara Rod as well on my trip to the Bob Marshall next week. I have the as yet unreleased 13' 6:4 model, it weighs 3.5 oz. I think the added length will be very nice for playing larger fish, which the short rods have a tougher time with, and for fishing the bigger rivers out there that we plan to hit - South Fork Flathead, Spotted Bear, S Fork Sun River, etc. Plus, with high water there, the longer rod may be more versatile for nymph fishing big water.
I'm very intrigued by this system for backcountry, and this next expedition will be a full test of how it will do. I can't wait to report back.
My rod, line, and tackle for this trip will weigh less than seven ounces ... pretty cool. In 2001 I was light at 24, by 2005 I pared down to 16, down to 12 oz in '08, so this will be another big jump for me, without sacrificing my love of fly fishing.