There are 2 points here.

1. The "a little too good to be true" hint already pointed to that. Nobody knows about you (yet). So in a way or another you'll have to get as many people as possible start using your product and review it.
But point 2 may stop many from give you a try.

2. You didn't mention that anonymity comes with a price. And the physical card is not cheap (one needs to send 55 EUR for the chance to get the card in hand). Also I guess that the 10 EUR monthly fee also apply for Virtual cards. This will not matter when Bitcoin price will get very (very!) high. But until then... it'll be a party stopper for many.