I just ordered a 09 Accord Euro Luxury Navi after also looking at the Mazda 6. The engine in the 6 definitely feels like it has more mid range than the Euro, but the Euro feels like it wants to rev more.

The interior in the Euro is miles ahead of the 6 when comparing model on model and this is what swayed my decision in the end. There is more room in the 6, but the Euro has a much more upmarket and solid feeling than the 6.