I tried this shop. cards are divided into 3 categories - high end , mid and cheap. I bought high end ones about 6-7 which costed from $10-$21 per card. Not much of high balance ones but regular. Validity depends on the sellers. I tried two cards from one seller and it was not valid. The other seller had valid ones but not worth the card amount. Also if you check cards back to back after refund you will get a message that " they understand the card might not work but they need to protect their sellers."
Additionally their site is terrible and takes forever to load and their tunnels keep failing so if you are about to buy or have bought a card and network disrupts you need to wait for a hefty time to get back in.