Roubaix .... do you like the Future Shock stuff/ Domane, is Trels version, i think. Cannondale offers the Synapse. All basically equivalent. I liked the Giant because of value .... better frame and decent components for less cash. I ended up getting a Fuji Sportif ... that and the CF version the Gran Fondo, also strike me as good values.
At any price point all the bikes will have almost exactly the same features. It comes down to specific needs and desires. Giant had a (reputedly) a better frame at a lower price point, which means when the original group wore out, upgrading would make sense. Trek, Spec, and Cannondale wanted more money for the same stuff. I went with the Fuji only because it just happened to be a Performance Bike Triple Points Weekend (now defunct, I think) so I got $300 free merchandise with the bike. I absolutely love the bike (rode it last night, in fact) and it has never let me down in anyway. i use it for rain, groceries, hauling heavy loads (50+ pounds) as well as general riding. The only things I have changed are the seat and seat post. it is the only unmodified bike I own---it is already there, there is no further I could take it, so i just ride it.
I rode with several Synapse owners who loved their bikes ... but only because of price, it never made my list.