Those are probably pretty good. Run one through dvdinfopro and see what the media code is to be sure. That will tell us a lot more. They are still pretty pricy though.
Incidentally, to change the book type of a +R you must also have a burner that supports that. I know that Lite-On will and Pioneer won't. Can't say about other brands since I've only had the two.
Meritline usually has about the best prices. Use their website to compare prices. http://www.meritline.com/