The only one of the 3E Ravenloft books I picked up was Van Richten's Guide to the Shadow Fey, and it was really, really cool. I did look over the hardcover in the store, as well as Denizens of Dread, and the hardcover was pretty good, though I didn't end up buying it. The main reason I wanted it was the fear rules, as well as the Vampire, Mummy, Ghost rules at the end of it, but I was squeezed for cash at the time, and couldn't justify the expense.
Overall, the books are pretty good, and I'd definitely recommend checking them out. I'm not sure why anyone would say they suck, from the ones I've looked at.
Banshee