I have been using Manhattan card. I am finding the experience to be on the whole good. Let me summmarise the good and bad points :
Good points :
a) No annual fee for life. Now, many cards have come with this idea.
b) The rules and regulations are clearly mentioned with no ambiguity.
c) Their call centres are most helpful
d) They charge minimum interest compared to all credit cards at 1.49%, if your payments are regular.
e) The ceiling amount is high at Rs one lakh.
f) Very prompt in sending the bills in time.
Bad points :
a) They do not have a website for their Indian operations.
b) They do make mistakes in debits, but they correct it once pointed out. For example, they charged a fee for card to card transfer, but when pointed out they reversed it. But I do not think these are deliberate.