I have a brand new 2007 Gary Fisher Tassajara "left over at LBS" It came equipped with a front Deore derailleur. I just recently found someone selling a front LX derailleur, but it is off a 2004 model bike."seller said its new he upgraded when he bought the bike to XT" Being there 3 years different in age, is it worth switching to the older LX. It will cost me 15 bucks plus I need the LBS to install and a 45 min round trip to pick it up. I just don't know how much they change from year to year, plus I also have a LX on my back gears. Any opinions would be great.