We hired a car for 2 weeks on Nov 19 2009, on arrival we signed a credit card slip for a "pre-authorisation" of 300 pounds to be re credited on return of vehicle and a slip for the full rental payment of the car. We have used this firm several times before and never have had the pre-authorisation deducted from our VISA card. So the mistake was partly ours, but after a long overseas flight easily made.
We handed the car in on December 2, 2009, in good condition with no complaints about damage. So far after numerous phone calls and emails they have acknowledged the "mistake" but failed to re credit the deposit. Always one excuse or another. We would not have expectd a reputable company to treat tourists in that fashion.
Unless this problem is rectified, we won't use them again and recommend that you don't either.