You are quite correct in what you say,but,in 2001 the UK300 was produced with 245ps(board on board chipset)241bhp,from 2001 X plated cars until Sept 2002 these cars were all 245ps,from then on most were 265ps using the updated ecutek technology,as this car is a Sept 2002 onwards car i would take that it was the latter pack,but you never know.
If it is the 245ps pack its no wonder that the car doesnt feel as sharp as even a standard classic.
Gav