I've used them 3 times and they've been great. They're very polite on the phone, it's easy to make a booking and they send you an e-mail confirmation within minutes. The drivers are friendly but not overbearingly chatty. This is an extreme example, but nonetheless an example of their exemplary service: one driver, David, was taking me to LAX for an international flight, which I was running late for. He patiently waited for half an hour while I finished packing. Finally we left, and drove for 1/2 an hour through rush-hour traffic towards the airport, but I realised moments before we got on to the 105 that I'd left my passport at home. He turned around, drove as fast & safely as possible back to my house calming me down the whole time and reassuring me that everything would be fine, then drove me back to LAX, and I made my flight. They only charged me $20 extra for this whole debacle, even though I said it would be fine to charge me twice. Pretty wonderful.