I put 4,000+ hilly miles on my old bike with Sora. No problems with it over all. Yes, the shifting is not as smooth as the 105 I have now but it wasn't horrible. Regular tune ups kept me content and on the road. There is nothing wrong with Sora or Tiagra, but maintenance counts!
Amanda
2011 Specialized Epic Comp 29er | Specialized Phenom | "Marie Laveau"
2007 Cannondale Synapse Carbon Road | Selle Italia Lady Gel Flow | "Miranda"
You don't have to be great to get started, but you do have to get started to be great. -Lee J. Colan