As far as requiring a credit card now for payment I think its better because now if some other driver tries to take your fare the only thing he gets at the end is the TIP BECAUSE YOU ALL READY PAID UP FRONT.
Um, I think not--we were left stranded at our hotel by this company last summer. We also had used it without issue for a couple of years. We ultimately had to take a cab just to make our flight on time despite the dispatcher assuring us for over 45 minutes that "our driver was there and you weren't" not so--we were early, "oh no, wait--he's on his way", "he's there, oh no--my mistake he's just outside the driveway". . .no driver showed up to take us to the airport. We were lucky enough to grab a lead footed cabbie and made it back to the airport just in time for our flight. We were where we were supposed to be and early to boot!
Now, if we had paid up front--we'd have been stuck paying twice for the last part of the trip. In fact, we were told that if we didn't wait we would lose the amount already paid in advance. Well, there's the rub--our driver wouldn't accept payment for the r/t nor would he take the coupon. Lucky for us he didn't or we'd have been out a chunk of money. The dispatcher's wanted us to wait (and miss our flight I might add) or lose what she thought we had already paid. We were lucky to have not paid in advance. To rub salt into our wounds, upon our return home, we had a very nasty voice mail on our cell phone from the driver insulting our ethics, intelligence, and character (with quite a few expletives thrown in for good measure). Anyone can make a mistake--no question, BUT you don't threaten the customer by withholding a return of payment (had we actually made one) when you are at fault AND you certainly have a tighter reign on your drivers--there's no excuse for that kind of rude, insulting, and vulgar telephone message when he was at fault!
I suppose you do have more grounds to complain, and therefore a bit more protection, if paying by CC because the dispute will be taken up by the CC company with the claimant. Still, that should be a customer's choice not a company's.