wow...taken this long to get a reply lol!
Well, it depends on what your game is like, if you're like me and play a fast, aggressive game then get a really light racket for matches and a really heavy one for training.
The reason is because you can get a lot more power after playing with a heavy racket (often wooden in my case!!!) when you revert back to your lighter one.
Whats your favourite style of game? Doubles, mixed doubles or singles?