Our local auction house told me that 1/3rd of purchase price is about average for a bike in ok nick
Apart from the debate on the relative merits and costing-out of the Rohloff vs derailleur drivetrains, this hefty devaluation of used bikes and my great sentiment toward any good tool (my bikes are indeed tools) is the reason why I rarely sell-on my older bikes. For what I would get for them, there is still residual value to be found in keeping them and riding them only occasionally. It isn't worth selling; a whole nicely working bike might bring half the cost of a frame alone -- if I were lucky.
As for the drivetrain debate and relative worth, all my bikes have derailleurs except for one Sturney-Archer 3-sp U-frame Folder, the Rohloff-equipped Nomad, and a moribund Sachs 3x7 on a Bike Friday I was recently given. Except for the Nomad they are all older bikes, most with 5-6 very thick cogs running on freewheels (and one 7-sp cassette) and similarly thick, non-indexed, hard-anodized chainrings. I get exceptionally good service life from these, but have found to my dismay I can wear through two or three nearly complete 9-sp drivetrains (most-used cassette cogs which are now part of a set and chainrings, plus multiple chains) in a single summer of my riding. Not so the Rohloff. It's longer life means I have already balanced costs and am now making money going forward compared to 9-sp. The increment is not so great compared to my older derailleur drivetrains, which I can keep going by reprofiling and heat-treating worn teeth every several years.
For me, the Rohloff feels more like a return to the "good old days" of long-wearing reliable half-step derailleur gearing. My 36x17 setup duplicates all the midrange gears of my favorite half-step setup but discards the useless higher gears I needed for the combo to work (but never used) while adding several much-valued lower ratios (which I use often while touring in mountainous terrain).
The icing on the cake is the exceptionally low maintenance required. I still clean my Rohloff's chain more often than most (little mascara brushes between the links while on-tour, with wipe-downs to remove grit before reoiling), but I'm spared the need to floss between the cogs and clean the gunk off a derailleur's jockey and tension wheels and I have more ground clearance and no fear of chainsuck in mud or hanger tearoff should the chain ingest a twig or small stick. Yes, my time is valuable, but I have a more Calvinist work ethic that says doing for oneself and working hard are not bad things, with more leisure allowing more projects and tours.
In extreme and continued heavy touring use -- torrential rains, mud, blowing talc-fine alkali dust, ground lava road-grit, snow -- the Rohloff really shines for me. I do have the continuing perception it is slower when coasting (not under drive), though I frequently ride the Nomad on 200km days where interesting detours to fire, timber-harvest and Forest Service roads call me away from pavement. For long day rides and less demanding touring conditions, I'm still happy with my older derailleur drivetrains and find the lighter bikes (key point) they're attached to better suited for 300-400km days in the saddle. A Mercury might change that balance, but I can't afford one. I do think common perception of the Rohloff
drivetrain is colored to a degree by the sorts of
bicycles they're attached to. Because they are so well suited to touring, Rohloffs are less often seen on lighter go-fast bikes. Also, the Rohloff rotary grip-shifter remains problematic for some drop-bar users because it is not as well-integrated as a derailleur's brifters, though it can be as convenient as bar-end shifters, depending on how it is located.
I think there's a place at the table for both drivetrains, but for the really gnarly stuff when I'm Out There Alone for a Good Long While, the Rohloff is the arrow of choice in my quiverfull of bikes and for me in my use, it especially makes sense compared to the more quick-wearing 9-sp derailleur drivetrains. Given this, I'm sorry to see 1x11 being developed, and would like to see the reintroduction of 3x7 or 3x8 touring-specific setups for the dedicated tourist. Until and unless, I think Rohloff is the way to go for long-lived all-weather touring.
Best,
Dan.