I did not know there was a problem with the merc reliability. My mate has a cl500 and has had no problems.
Dont want an audi TT. I dont like them. Been looking on parkers web site. They are of the opinion that the 3.0 is a far better buy that the z4m. Not as harsh, not as expensive, better fuel, cheaper to service, cheaper insurance, Not much gain in performance from the 3.0. I am being swayed towards the 3.0.