The Madone 3.1 and the Synapse Carbon Apex are similar bikes at same price point. Ride them both. Does one fit better than the other? BUY THAT ONE. Do they both fit well? Buy the one you like. They look quite similar: 50/34, 11-32 gearing. 23mm tires on the Trek, 25 on the Synapse. The Trek is H2 fit and might be a bit more aggressive than the Synapse. I picked up my Synapse yesterday and took it on it's first ride today and it's a SWEEEEEET bike. The Trek was my second choice. You can't go wrong with either one.