i just got my first amex 2 days ago. im so happy i got to be part of the amex family. perfect card since i want something with rewards and pay every month. since it has no pre-set limit? does it mean it really has none? like from 0 to whatever? i read some people that has zync got a 250 limit.. isnt zync a charge card too? how come it has a limit? i need to know more how charge cards go. any advice?