Let's talk about cardstock for a second. Pictured above is my beloved Prairie Tarot. I've had it since December. In the months since then, pieces of the edge of the card have flaked or pulled away, causing these messed up edges. This is called "foxing", and it sucks. It can get bad enough that your cards can start snagging on each other and will tear. (egads)
I don't think that this much of a is a problem for casual tarot readers, but professional readers really have to keep an eye out. I love this deck and wanted to make it one of my 'working' decks. I do at least 10 readings a week, and I can't count on this deck lasting as long as I'd like (10 years would be ideal) if it's already foxing after four months. SO that means that I take it out of the rotation for parties and daily readings and hold it for private readings or classes. That sucks.
When I do deck reviews, I'll always remark on the cardstock because it's important information for readers. I would love it if publishing companies would put more thought into the usage of tarot cards when choosing the stock. ESPECIALLY for decks that are black or any other dark color.
The best decks I've found in this regard, btw, are the Golden Thread Tarot, the Wild Unknown, and the Fountain Tarot. Not coincidentally, they are my most used decks and will likely be around for a long time.