In my very humble opinion, for whatever it may be worth, if you keep anything for long enough it will become more collectable and, by default, more valuable. However, in the short to medium term I am not convinced that this particular model is the best investment for a modern Tag Heuer watch; there are other Carrera models out there (such as the Jack Heuer Limited Edition 40th anniversary model ref. CV2117) which are prettier, rarer and more sought after and consequently a better watch to invest in. I think that the watch that you are looking at is a really good looking piece which draws a huge ammount of influence from the original but may not be the best model for appreciation.
Good luck
Jon