ok, i've been messing with this card a bit and will tell you my experience whether or not it makes sense. i'm using it fine at scotia bank. the bank shows no transaction fee at the atm. when i log in to green dot to see what i was charged - it show 50 u.s. cents for a foreign transaction fee or whatever, but then, two days later an atm charge of $2.50 u.s. shows up as well.
so i guess it's $3.00 u.s. to use it. here is another cool thing i didn;t know you can do. you can have your money in paypal sent to the card by adding it as a bank account. i think that is really cool.
OHH! but it costs $4.00 U.S. for the person on the other end to buy the card, so it might not be such a good deal for many people.