Sounds like the little thumb buttons on the Soras is some kind of Shimano ploy to get you to go to the next level. I've only had my current bike for about five months but I guess considering I now know that cycling is something I love and will probably continue to do for my whole life, it would be worth a possible setback of $4-500. What are your opinions on the different brands out there (I understand that this is a ridiculously open ended question).

Thanks