car rentals in UK?

["Fadeev, Alex" <Alex.Fadeev@xxxxxxx>]

Folks,
I will be in the UK in a months' time and will be renting a car for a few
trips.
Can any of the UK based digesters suggest a good place to rent a car near
London (other then Hertz at the airport;-)?
Money concerns are secondary to the fun factor. Particularly if I could rent
something in the 3-series size that is not available in the US (Alfa
156/convertible/etc)! 

Any suggestions would be most appreciated,

TIA,
alex f

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