The new one may save you some money over the summer.
Tires $50 - $90 each
Chain Dura Ace $45 aprox.
Cassette $75 - Sky is the limit here
Front Sprockets guessing at $50 each.
Bottom Brackets can be expensive also.
Both of my road bikes have Dura Ace components. I know what this equipment costs as for Tiagra cost I am just ball parking.
Wait until you see how fast you can go.
Vancouver is made for bikes.
Olympics thanks for the show. I must have been great to have the worlds best in your town. You put on a great show.