I read a couple of JW books when I was a girl, but mostly I got fed up with them. from the age of 8 or 9 or so I hated reading about the real world; I much prefer to read fantasy. I can remember reading a book where a character's parents separated and they wanted them to get back together, and wishing my parents would as well. The fact that it happened in neither book nor real life was the final straw for me. When I read, it is usually to escape real life, to go somewhere else and, for a while at least, not have to worry about my RL problems.
That said, I don't think they are bad books at all - just not for everyone, the same as no genre is for everyone. (Although I second a poster upthread recommending a search for Mark Reads, because - IMO, again - he is amazing. And Tamora Pierce's books are too.)
I think YABU to ban an author's entire works, because I don't believe in banning books at all. I mean, okay, keep them out of reach if they are age-inappropriate. My 5yo DS is not allowed to read all the books on my shelves yet, because the content is too mature for him. But when he is old enough that he can cope with it (he's slightly oversensitive so I am pretty sure I will have to 'police' him a bit longer than other children might need it) he will be allowed to read whatever he likes. I will step in and tell him I don't think a book has a good message if he chooses to read something legitimately harmful (As Twilight et al can be IMO, for the undercurrent of stalkerish behaviour etc.), but I think the finest way to ensure a child reads something is to ban it, so what's the point, aside from anything else?
I had a friend at school who wasn't allowed to read Harry Potter as her family were very religious. So she borrowed them off of myself and another friend, and stowed them under her bed, only reading them at night. The idea of banning books always seemed a bit pointless to me after that.