Hi Barry!
You're already received some excellent suggestions and great advice, and by waiting a bit to answer, I get to type a little less.
Truly, Barry, the bike you've spec'd is a Dream Machine, the envy of many, done to a top-level standard. As you know, I am big on personalization and on people getting the bikes they wish to meet their own needs, wants, and desires. If you can afford it, get it! If the cost is becoming a bit dear, then I do see some areas where a reduction or two could be made without feeling it in daily use, and can add a few suggestions that might prove helpful beyond those nicely offered by others:
Color: Get what you wish, as there is no extra cost and you will be enjoying it each and every ride. The yellow looks simply fantastic.
The S&S couplings are a large expense for something that is generally used infrequently. If you truly won't be breaking down the bike very often (say for storage or to fit in transport), then you wouldn't often miss this deletion. If you genuinely think it would help for your use -- and it did greatly, even once -- then it might well be worth it.
I think you are wise to leave your tire options open when specifying mudguards. Yes, it might look a little odd to have mudguards so much wider than the narrower tire size, but look at it this way: Aesthetics aside, this is a very smart move. No one ever mourned having better coverage, and you'll save having to purchase and fit wider 'guards at a later date. I would suggest you make your plans and desires clear and in writing to Thorn so they can refer to it during the build...and ask if they will also
leave sufficient clearance 'round the smaller tires to fit larger ones later. You won't want the wider 'guards snugged down tight over smaller tires, else there won' be room for larger, later. Putting this and any other preferences in writing is a tremendous help for the assembler to have for reference.
The anodized hubs at either end will stay looking nicer over time if you are not an inveterate polisher of bare aluminum or if you ride on salted roads. I chose anno'd black to better resist the effects of corrosive alkali playa when riding in the desert.
I started with 40x17 gearing and went to 36x17 as soon as Rohloff approved it. I am so glad I did! Top gear is a realistic 80 gear-inches, and the 15in low is also genuinely useful for me when climbing steep hills with a very heavy touring load. Dropping to 36x17 not only gave me useful gears at either end, it had the benefit of placing all the intermediate gears where I needed them. Beyond this, it provided two distinct ranges -- a High range of 37-80 gear-inches for general use and cruising that operates silently and a Low range of 15-33 gear-inches that hums along a bit in some gears and is ideal for hills of all types. It has worked out very nicely for my needs, but of course would not be suitable for everyone. The good news about gearing is, if you've made a mistake, it isn't cost-prohibitive to change it. You could go with Thorn's recommended 38x17 now and if it proved too high, a new chainring would put it right.
There is no better value in Brooks saddles than the upgrade deal offered by Thorn. Well worth it and then some. If for some reason you and the Brooks don't get along, you can always sell it on for more than you paid. The B.17 is my favorite, but I also ride with a preferred 45° angle to my back. Andre is correct; if one rides upright, a wider saddle is more appropriate.
I'm fussy about brakes, and found the basic Deores have proven surprisingly good for my needs in use; the upgrade to XT was not worth the extra expense to me, but many people feel it is worthwhile. If you didn't have the CSS Andra rims, I would suggest Kool-Stop Salmon-colored brake pads. Where you will be getting the CSS rims, then you will need to specify the SwissStop blue ones (or Thorn may well do so for you at time of build so the pads are appropriate to the rim). I mention this detail only because I didn't see it in your specs.
A dynohub and charger are essential to my own use, and their merits are discussed at length on Forum boards devoted to them. Please refer to the Lighting and Electronics Board (
http://www.thorncycles.co.uk/forums/index.php?board=10.0 ) and the child-board devoted to Battery Charging from a Dynamo (
http://www.thorncycles.co.uk/forums/index.php?board=32.0 ). To make sure you get the greatest use and value from the Forum, it is worth spending a few moments looking at my search tips article posted here:
http://www.thorncycles.co.uk/forums/index.php?topic=4390.0I hope something in the above will prove helpful in your considerations, Barry. You've spec'd a wonderful machine, and it should meet every possible need and exceed all expectations. Please don't hesitate to ask us if any questions develop between now and purchase. "Crowd-sourcing" solutions is a wonderfully efficient way forward, drawing on the collective wisdom of our membership, a good bunch all.
Best,
Dan. (...who thinks vicarious bike spec'ing is a participant sport on this Forum and loves every moment of it!)