Has anyone experienced problems with South Florida Limos?

We hired this company to transport one of our best clients to Miami Airport and paid them in advance, including a 20% gratuity for the driver. We asked them to provide the best VIP treatment. Instead, the limo driver embarrassed our client by demanding payment of $102 for a 10-mile ride that was fully paid already. When I contacted the company, they did absolutely nothing about it and promised, but ultimately failed, to draft an apology letter to remedy the situation. Has anyone used this company and how was your experience with their services?