Several I guess. There are those that are most difficult to get a meaningful read, and those I can read, but aren't pleasant to do so.
Impossible for me: Bosch (just poor artwork that I couldn't make sense of), Botticelli (ack, the gold glittter everywhere I can't see!), Thoth (really cool artwork, but the colors and images made me feel ill - wish I had kept it to try again... I think.), Medieval (the glitter again), Nostradamus (whaaa?).
Difficult: Shadowscapes (great great imagery, but so tiny it hurts my eyes and I cannot relax and be intuitive), Wildwood (the titles don't work for me, and the court cards I don't get, but I have had some great readings when I didn't draw certain whaa? cards), Universal Waite (the artwork just doesn't work for me, flat lifeless doodles). Others that went to the recycle bin... ( I am an impuse buyer too often).
Sorry, that was kind of tough... I'm having a rough day at work and its finally over.