The Roubaix is going to need a tune up at minimum, possibly a minor rebuild. Stored bikes typically don't get regular maintenance. If something is broken or maladjusted, there is no warranty. You will most likely have to pay to have the bike fitted for you. If you are going to participate in a 9-day event, you are going to want to have the best fitting that you can get.
The Secteur will come with a warranty. When you are buying a bike from a bike shop, you can usually deal with them and get your fitting done on the house or at a steep discount. The first tune-up is usually free and is necessary because as the cables stretch to their final length, the components that they drive need to be adjusted to compensate for it. The Secteur is considered to be a plush road bike which means that it is a little more comfortable to ride than a true racing bike which is what the Roubaix is. The Secteur is not going to make you slow, but it will take a little more energy to attain the same speeds that the you will with the Roubaix.
If you want comfort and the local bike shop support, get the Secteur. If you are experienced in bicycle maintenance and repair, fitting, and you value speed over comfort, get the Roubaix.
