Applied for this card and was approved for $1k a year ago. After using the card on a regular basis and making regular payments (about 3-5 per month) my credit limit was increased to $3k in just 6 months. Continued using the card on a regular basis, making payments on a regular basis and today 6 months after my initial increase, AMEX increased my limit by $6k. I now have a $9k credit limit! My score when i applied for this card was about 650 and since then has increased to about 730 in one year.
Great card, use regularly and make more than the minimum payment and your limit and credit scores will increase. AMEX has no limits on the amount of times you can make payments. This has helped me tremendously. I would recommend even if you have a very low limit, make a payment as soon as that charge reflects on your account. You dont have to wait until your statement appears in the mail. Stay on top of making those payments and your limit and scores might increase.