I've been looking at the 520 and the Surly LHT. I got a lot of great info from the net. MANY people came to the same conclusion: Great bike but get new seat, gearing, tires and rack. Most people did upgrade after they bought the stock bike and wished they would have upgraded a few parts right away.
My local Trek dealer was great. He said he would have no problem with upgrading as long as I didn't take it for 250 miles then want to upgrade. He did say he'd only give me $5 toward another saddle. Wow, stock seat MUST be bad!
However, I didn't ask what credit he'd give me on gearing, etc.
EVERYONE says gearing is brutally high on a climb. Many recommend 26 (30 is stock) and some go even lower.
Some big dudes (>225 lbs) suggested beefier wheels. Trek dealer was surprised by that one and said stock wheels are fine for my 210 lbs. This gave me confidence he was being straight with me.
Conclusion: Great bike but they are trying to keep price down and a few parts need upgrading presuming you are touring. Upgrade so you don't have to buy things twice.