A little more information please. What I can assess is that you want a road bike that you can ride a century on. Are you leaning more towards performance or is there a little room for comfort. I have two road bikes, a classic steel road bike, performance geometry but still very comfortable on long rides. I also have a performance road bike (CF) - stiffer and lighter but not as comfortable on longer rides. I do not have a Ti bike, I suspect they would be a slightly lighter ride but similar to steel and a good choice.
I would look at a Serrotta - they are known for comfort and performance.