I'm going to skip back to the first post and forget about most (but not all) of the rest. If you know what you like in a bike such as bars, seat, seatpost, brakes and shifters, tires, wheels, etc. I would not go with the complete (Surly) bike. After a period of not riding, I decided to start back up and tour. I was a previous backpacker, so I knew what I wanted to do which was roll a whole bunch instead of walk. About 10,000 miles later I have made quite a few changes. I want to make more, but I'm kind of like, "If it ain't broke, don't fix it".
I keep on looking at the stock wheels and think, well, I could spend some $$ and get some lighter ones that are probably just as strong. Or many other things could be replaced the same way. Then again, I've hit so many potholes and they are pretty true, think I'll keep them a while.
Only other thing I can think of, if the frame has the qualities you want and has the proper fit *AND* you just like it and think it's for you, you can put whatever level of components you want on the bike. Then again, I don't know you. If you plan on hauling 4 panniers and a case of beer, just go with what works well and will last a long time.
Additional note, I need around 16 G.I., don't use it very often but when I do.....