I have bar end shifters on 3 bikes (including a surly cross check) and love them. True, you can't shift as quickly in a pace line, but otherwise (and since I don't generally do that kind of riding), they're great- a little less fiddly (and you can always shift the rear to friction if it gets out of adjustment). I find them more robust than STI.
I bought by Surly off ebay - and had never ridden one. I lucked out with fit - bought it off a couple of key measurements. I think it could work for your son to order one sign unseen *if* he has a local dealer that will do a fit kit on him. They should be able to tell if it will be a good fit for him, and they may be able to duplicate the geometry on the fit kit and/or let him try a bike that's similar in fit. When you order a custom bike, you can't really test it either. The key is finding a dealer he can trust. I can only think of 1 shop within 4 hours of me that ever stocks built frames - I think most buy sight unseen. Good luck!!!
CA
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