This is by far the most satisfying of all Tolkien calendars, because it is the most real and personal rendering of Middle Earth by any artist.
Alan Lee and others have done some good work, but this was Tolkien's world and these are his images. Sure, Orthanc is less severe in Tolkien's imagination than in Jackson's film, but Orthanc was never intended to be portrayed as an evil fortress? Originally built by Men of Gondor, Orthanc served as an impregnable fortress. In Sindarin, it means `Forked Height', in reference to the four pinnacles of `hard, glossy black stone, welded into a single tower five hundred feet high'". It was later deserted as the Dứnedain moved north, and Saruman - ever in need of feeding his ego - took up residence there. For those familiar only with the movies, this drawing might seem like a let down. I hope that I've squared this away somewhat. The movie overdid it.
I have always admired Tolkien, revered him with a sense of awe. He wrote a classic children's novel (The Hobbit) and another less well known children's book, Letters from Father Christmas (which he also illustrated). He wrote one of the most influential novels of the 20th century, The Lord of the Rings, which was not only a remarkable work of literature but spawned an entire genre (and, unfortunately, some rather poor imitators). Beyond that, he wrote remarkable poetry, much of which can be found in The Hobbit and The Lord of the Rings, and in The Lays of Beleriand. But wait - there's more. He wrote mythology. Mythology that is to me, at least, more interesting than any existing "real" mythology. I'm referencing The Silmarillion, of course. As if that isn't enough, Tolkien was an accomplished artist, an Oxford don, translated Sir Gawain and the Green Knight, and held various chairs throughout his illustrious scholarly career. (Where in the world did he find the time to do all of this?)
As to the calendar, Rivendell's beauty is captivating; Lothlorien is as it should have appeared in the movie; Fangorn, with its dark, oppressing watercolors is frightening and foreboding, a forest one would be wise to avoid; Helm's deep, while less impressive as a work of art, is unique as it offered Tolkien a visual image from which to work while planning this massive battle; the leaves from the book of Mazarbul were perhaps my favorite inclusion, if for no other reason that it caused me to admire Tolkien even more; Minas Tirith, though unfinished, showed signs of grandeur; and the covers that Tolkien himself drew for the three books are better than any I have seen. The drawing for the Two Towers ends the debate of exactly which towers Tolkien was referring to in the title. He drew Minas Morgul and Orthanc. I think he's the expert on this.
Honestly, I'm not sure why The Brother's Hildebrandt bothered to put out a LOTR calendar. I'm sure it had to do with milking the 50th anniversary for all its worth, and that I haven't seen their names on anything of merit in years until the LOTR movies were being made, but their art doesn't come close to depicting the depths of Tolkien's work. They were best served as artists for The Sword of Shannara - which was derivative and shallow. If you're thinking about which calendar to buy, stop thinking right now. This is the real thing - the other is simply Parkay.