I opened a Stingers deck, and they were completely useless for magic within 2 hours of practice. Bent, completely unable to handle, couldn't fan, utterly warped, so much so that it was the size of 1 and a half decks sitting flat on the table (i say flat... it was too bent to sit flat on the table). I couldn't do a double because the cards were so irregularly bent, couldn't do an elmsley cause they stopped sliding.
I wouldn't normally criticise a deck of cards but they were just so shockingly bad.