Yeah, its a difficult decision.
I have an 05 reg which has only done 18k miles. I live in London so I wanted a nice (reasonably rapid) car which at the same time doesnt cost an absolute fortune to keep and I can sleep at night knowing its parked on the street. I can see myself keeping it for the next 2-3 years.
Its niggling at me. The spec is as I want it if I was speccing the car from new except for the engine upgrade. I know I could move up to a used
JCW for less than it costs to do the upgrade but I wont get the interior spec I have, which is pretty much everything.
To a certain extent, the money isnt the motivating factor.