Alas, my review is of Citibank, not necessarily this card. I have no doubt that Citibank has many happy customers who use reasonable quality credit, otherwise they would no longer be in business.
Howevver, with that said, I have struggled with Citibank for three years and unfortunately, I fell into "fool me once, shame on you, fool me twice, shame on me." I blew past twice and kept going back to them because I liked the benefits of my card.
Over the past three years, I have found customer service to be unhelpful and at times rude. I have found repeated occasions where policy is stated, but cannot be provided in written form, to deny any kind of action on the account from credit limit to APR action. Citibank will tell you that accounts are only reviewed twice a year, and that certain account actions are automatic at those times (they aren't). And, if you want to make certain types of account changes, there are only two months in the year that you can do it (not true -- but if you miss those months, you have to wait for the next one).
I have had them provide false information, make unwanted changes to the account without warning and refuse to escalate customer service calls to higher tiers. I've even had them lose online payments, even though I can provide transaction numbers, and ding the account with late fees (which, by the way, automatically triggers a lockdown on the account, so you can't make any positive changes to it again). Citibank is also the only card that raised my interest rate for no stated reason, and refuses to lower it claiming they "can't". To date, my Citibank card is significantly higher than my next highest account, and all other providers are willing to negotiate terms.
All in all, Citibank customer service (not the individual employees) is among the absolute worst that I have ever encountered and although I still possess the card, and will wait for the day when this company returns to the world of valuing the consumer, I am pleased to have paid off my balance with Citibank and maintain a zero dollar balance.
P.S. Watch other accounts carefully -- Home Depot and other cards are actually issued by (or occasionally purchased by) Citibank, and some of those same experiences start showing up on those accounts also.
Sometimes it's not about the card and benefits it provides... sometimes it's about the company that is behind it. As long as you're aware of it, you can make better decisions should anything go wrong.