I can move from a 99-00',is it worth it?

[Perfectlap]

2.5 to 2.7 not such a big jump.
2.5 to 3.2 you will feel a big difference.

If you're condisering trading up (a good move the market is good for buyers now and getting better) I would wait a little longer and get an S with low miles that is at least 3 years newer than your current car.

Pick up a copy of Excellence at Borders or Barnes & Noble. They have a market review guide where they explain the differences between model years and different values.