I bought my Synapse 3.5 months ago, but didn't know too much about road bikes. I went with the comfort and feel of the bike (over several others) and also happened to get a triple.

After 3.5 weeks of working out, losing 10 pounds, and not using the third ring much, I had just gotten to the point where I thinking "maybe I should replace this triple with a double". Well, some hill repeats today changed my mind! I stayed in the middle ring for most of the hills, but there were two that I just couldn't do without moving to the third ring.

So, if you're on the fence, I would suggest get the triple. You may get to the point when you won't need it. Maybe then you can move to a double. And, think of it this way, you did all that practice on a heavier bike (although I don't think there's that much weight difference between the triple and the double) and will be better when it's lighter.

Good luck!