Thank you all for your thoughts. I would look at a 250 as first choice but the tax and contribution make it an unattractive option.
I have just done back to back test drives with the BMW 320D , my exis merc C180 auto petrol and the lexus 220D. at the risk of turning this into a "fuel fix" thread.
11 mile run from middle of estate - windy road - motorway - to steep hill - extreme windy hill to town driving up one final hill 30mph due to speed cameras.
The above is my route and felt it would be a good run to test comfort, drive and economy.
So the findings
My Merc petrol. (51k)Avg Speed 34 AVG MPG 28.2
BMW (4.3k) Avg Speed 32 AVG MPG 35.9
Lexus (2.9k) Avg Speed 30 Avg MPG 29.9
Now I know the 2.2 engine and weight of the car would be against the lexus but I expected it to be further from the mercedes than it was.
Ride - very comfortable in the lexus though a little more roll in the windy roads than expected. BMW, not a family cruiser on 18" runflats bumo bump but very planted and certainly more fun throwing in the corners.
Overall I like the Lexus as an overall package and the family man in me says cruiser (though will I ever cruise in 6th!) though with the extra premium to pay in the petrol and the loss of MPG I cannot help but feel that as both the BMW and Lexus will cost me the same overall in contribution (though lexus with a lot more kit) the running of the lexus will be astronomical in fuel compared.
On another note why do lexus do a flat black only? Like the black but worried it could look quite flat if I dont wax too much, silver every other IS2xx seems to be this colour do not really like anyother than Cadoxton Slate
Thanks for reading and fel free to support/flame