I've used them and no problem giving them your credit card details etc, but I only used them once, and found if you steer away from the standard "I want a room", then they get it wrong, they ignore requests that you insert on your request form. For instance, WE wanted 2 rooms in Sydney, and paid for them, when we got to Sydney, ooh sorry thought it was one room for 2 of you and "they didnt say anything about non-smoking" - eventually sorted, but annoying all the same. Best to ring the actual hotel up a couple of days before staying there to confirm.