Andy, I'll echo what's been said by others who have more experience with Rohloff hubs than I have (one year, this past season).
A few things to add, however:
1) It's much easier to change gear ratios with a Rohloff -- a matter of changing only your single chainring at the front, and/or your sprocket at the back.
2) I have much less experience with touring than many people on this site -- only about 10 - 12 years. I bought my first touring bike in 2002: a really good quality locally spec'd (Eclipse) ti-framed light touring bike with carbon forks. I still have it -- now, however, it's mainly for day rides, displaced by the Thorn Raven I bought a year ago. In the 10 years or so I used the Eclipse, I used three power trains, all Shimano: 105, LX, and now Deore. The price of those, taken together & including labour, exceeds by about 25% what I paid for my Rohloff from starbike.com.
3) Why three power trains, you ask? Part of the reason is that, if I knew then what I know now about bikes, touring, and my own interests & tastes, I would not have spent so much time experimenting, trying to find what suited me best. I didn't always get the most appropriate advice, and my needs/tastes changed as well. BUT, the biggest part of the reason I opted to get a Thorn + Rohloff is that I have had way too many hassles with derailleur maladjustments -- sometimes in the middle of tours, sometimes at home, close to my LBS and/or my workshop. My experience is probably worse than many others', and to be sure, nothing catastrophic ever happened, but it was just like getting nibbled to death by ducks. No fun, hauling yourself up a 13% hill, having to go for your low x low, and not at all confident you'd get it.
After learning more about the care and feeding of derailleurs than I really wanted to--and people like Dan were very helpful and patient with their wisdom and excellent technical advice--I said, "Sod it, I don't need this."
4) When researching the cost of the Thorn + Rohloff, I realized I could get two well-equipped Surly LHT's for the price of my Raven. Neither one, however, would give me the low gear-inch setup I have with my 38 x 17 Rohloff, or the option for a lower-still lowest gear with a 36 x17 (see above re: ease of changing ratios) while still giving me ready use of suitable intermediate gears. Without getting into too many numbers, my current setup on my Eclipse is 24 - 26 - 46 at the front, and 12 - 36 at the rear (700 c x 32 tires). This gives me a low gear-inch of 18.3 -- rather higher than the 15.7 on my Raven. I'd like to get a 22T small ring on my Eclipse, BUT, the middle 36 ring works well for at least 80 % of my riding, and I'm not at all sure that my front der would handle the 14-T step-up between the two; while going to a 34T middle ring would mean I lose the flexibility that the 36T ring offers. So, neither of my half-price Surly's would give me the gear ratios I wanted; and, after literally years of irritation from forever maladjusting derailleurs, I bought a Raven-with-Rohloff.
5) No regrets at all, and the Raven is much more comfortable & functional as a touring bike than my Eclipse. The weight, interestingly, is little different: My Eclipse weighs just shy of 30 lbs (with one rear rack, two lights, plastic fenders and a small tool kit), and my Raven about 31 lbs with two racks (F & R) and a handlebar mounting bracket, two lights, alloy fenders, leather mudflaps, and a dyna-hub. The bikes feel very different, because the seating & bars set-up is different, as well as wheel and tire size, and brakes.
Hope this is helpful, though I recognize that riders have different needs, tastes, and interests, not to mention budgets. Good luck in any case.