One of the things I think many younger riders or newer riders fail to appreciate is how quickly technology moves in the bike world. It does not surprise me at all that today's Tiagra group-set functions as well as your four year older 105/Ultegra mix. And, as most of us have come to understand, it's not so much the frame material as it is in how well that material is being used. Lastly, you've got a bike that fits you properly. I'm glad you like your bike alot... it sounds like it's going to be a winner for you.
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A conclusion is the place where you got tired of thinking. - S. Wright
Favorite rides in the stable: Indy Fab CJ Ti - Colnago MXL - S-Works Roubaix - Habanero Team Issue - Jamis Eclipse carbon/831