Just fab is a legit company. I would never give my payment info to any company, except they have commercials on TV here in Canada, so I know they've got some credibility.
However, they advertise in Canada as if the person watching were in the US. $39.95 shoes, and don't mention just HOW they really make money. When you buy your first item whatever it is, they automatically register you as a VIP member, which means now your account is charged $##.## a month. In the US, it's $39.95 a month. If you don't want to get charged monthly, you have the first 5 days of the month to just "skip" the month, and they won't charge you. However, many people forget, and get charged the $39.95.
However, in Canada, because of exchange rates, my monthly fee would actually be closer to 60 bucks. Also, we don't get free returns and exchanges. We have to pay around 8 bucks to return an item for a refund or exchange.
In the states, this company is just marginally worth working with, because you could basically go down to forever21 or charlotte russe and get the exact same thing but here we pay like twice for shoes so it's worth it for me as long as I remember to Skip the month! If not, OUCH!