[Juerg]

The 04 is just a completely different bike from any previous R1, not because of its superior performance but because of its rideability. It is night and day, compared.
I'd strongly suggest a 04 if you intend to ride in twisties/on track, if not, the 03 will make you happy as well (it will anyway, it is a good bike, the 04 just is much better)

 

[Juerg]

you can even outrun many lesser skilled riders with 04 bikes

On a straight line maybe (however it doesn't take a lot of skills to just open up) but the 04 suspension is light years away from the 03 and the whole package, despite its higher performance, is much easier to ride. The older R1's are "bitches" to ride fast, many ate dust because that massive torque low down was to much for the rear suspension.
But I agree, it surelly isn't worth getting into financial problems, the 03 is a great bike as well.