I completely understand her wanting to write under a pseudonym (but that was a bit short lived). Especially if it's mysteries for adults. Yes I liked HP, but I was in still in junior high'. I tried to pick one up again, it's clearly written for teenagers (though not the worse). It's well written but the plot doesn't hold much surprise. And the last tome was... craming all she had forgotten to tell in a number of pages that could be published as one volume ^^.
Based on her "fame", I would only read one of her books if I was looking for something to recommend for teenagers. If I were looking for mysteries, I would probably dismiss her book if written under her name. Otherwise... I might read the reviews ^^