I ride one.
Here is my assessment.
The belt and the Alfine = super low maintenance. I can feel a little power loss with the belt, but it is silent and easy to maintain (especially with snowy, rainy, muddy commutes)
The shifter is adequate but is not nearly as responsive as what I am used to.
The BB5 brakes work poorly with road levers. They are awful to adjust. I suggest upgrading to BB7s as I did. (BB7s are great btw).
The frame is not light. This combined with the weighty rear hub, make for a heavy bike.
Bike handles heavy loads (40 lbs of groceries) comfortably.
The bike is not very fun or zippy, but the ease of maintenance, comfortable geometry, and all-weather stopping BB7s make it the best commuting bike that I have owned.
If I were to do it all over again, I would consider the Trek Soho Deluxe as well. For the time being, internal hub gearing and crappy disc brakes work better with flat bars.