I purchased the regular DVD set online, at DeepDiscountDVD.com, despite having a blu-ray player. This was mainly because there are a few more discs, covering material not covered by the blu-ray set, and at a lower price. Also saw it at Costco, for an even better price, though I haven't seen it there lately.
I enjoy them. The menu music gets incredibly monotonous. They are ads, something my wife loves to tease me about. They are great for the pretty pictures, but don't expect documentaries. If you can NetFlix them, so much the better.