To preface this review, let me state that it is in no way a comment about the films themselves. They are all wonderful. The two stars are for the packaging and content of the Collector's Set, which arrived at my door about half an hour ago.
I've had this on pre-order since it first appeared back in July of 2012. I never canceled my pre-order, so I ended up getting it for $139.99 (plus tax, now that Amazon has to comply with tax code). Would I buy it again for this price? Well, probably, because purchasing each of the film versions included individually would cost almost $200, so you're getting a great price cut on the whole set. With a savings of nearly $60, why would I only "probably" buy it again? Each of the discs is packaged in a glossy cardboard sleeve, and on delivery, some of my discs were already scratched from sliding. All of the disc sleeves are inserted with the sleeve openings angled towards the back of the case, resulting in sliding during shipment and storage. You can save money with this set, compared to buying each film individually, but you may end up spending more money by having to replace scratched discs. If you look at the product image, the two gaps on either side of the cosmic cube are where the film inserts slide in for storage (again, at an angle).
That brings me to the cosmic cube itself. Again, if you look at the product image, you see a very bright, solid light coming from a semi-transparent cosmic cube. The cosmic cube itself is very cheap plastic, and is heavily frosted, to the point that it looks like a solid white cube. As for the light, it emits nothing close to what is pictured. While mounted in the case, the cube is lit from below by two blue LED lights when the case is open, or when the button near the case handle is pressed (which is only useful when the case is closed, to backlight the SHIELD frosted logo on the case front, and the button must remain pressed for the backlight to activate rather than acting as an on/off switch for sustained illumination). Being backlit when mounted provides a very dim, almost imperceptible blue hue to the cube itself. When removed, the cube can be activated by "tapping the cube firmly once against your palm" for the first stage, and "tapping the cube firmly a few times against your palm" for the second stage. The first stage is never activated by a single tap, and the second stage is never activated by a few taps. Quite a few hard slaps will result in the first stage activating, which is simply a blue strobe from within the cube. The second stage is also a blue strobe, but with a faster pattern. Activation of either stage will result in a sore palm and severe disappointment.
The case itself seems sturdy, but if you're expecting it to be metallic in any way, you will be disappointed (which is a common theme with this collector's set). The case is a strong plastic, but does not have the shine and heft of a metallic case. As I said earlier, you do have a frosted SHIELD logo window on the front of the case that can be illuminated by pressing a button located near the case handle (the "Avengers" button seen in the product image), but it is again only illuminated when pressure on the button is maintained. It can not be turned on and set on a shelf for display purposes. The clasps have no hinge, but are simply hard plastic that must be pulled on to release. This will inevitably result in snapped clasps, as hard plastic can only be manipulated for so long before weakening. Last for the case itself, the panel that mounts the cosmic cube and the discs is a very cheap plastic. The buttons on the keypad have absolutely no give to them, as they are hard cast. There is also not as much of a color difference between the buttons and the pad itself as can be seen in the product image.
Finally for the product as a whole comes the dossiers. The dossiers are stored in the top of the case, against the frosted SHIELD window, held in place by the black panel with the "A" logo. This set of documents includes a "Confidential" sealed envelope (not pictured) that contains a "Field Agent Access Code" on a hard card, the size of a gift card, and a 4x6-ish holo-card with some blanked out information. I have not yet solved this puzzle, but I assume it directs you to a website where your access code can be used for additional content. The first dossier folder contains pictures and a info sheet on the cosmic cube (or the Tesseract as they call it in all of the documentation), personnel files for Hawkeye and Black Widow, and Agent Phillip Coulson's SHIELD business card. The following dossiers contain information on Captain America, Iron Man, Thor, and the Hulk, in that order. The dossiers vary by character, with references and items from each film. For example: Steve Rogers' dossier includes his 4F stamped application, physical exam sheet, some Captain America trading cards, and his drawing of Captain America as a performing monkey; Tony Stark's dossier includes a newspaper clipping, his original schematics for the Iron Man suit, a large folded schematic for the original arc reactor designed by Anton Vanko and Howard Stark, a ticket stub and guide to the Stark World Expo, and a bar napkin announcement to Stark Industries regarding the end of weapons development; Thor's dossier includes his medical bracelet, the drawing he did of the realms, Jane Foster's work badge, Thor's fake driver's license (Dr. Donald Blake), and a torn page from a children's book about Bifrost; Bruce Banner's dossier includes newspaper clippings and various other items (it's the weakest of the bunch). A certificate of authenticity is also included. Honestly, the dossiers are the most well developed and presented part of the entire collector's set.
So, back to the top: would I buy this again? Now that I've really gone through it all, I might not. I could buy the Avengers Six Disc Blu-ray Collection for $109 and save myself $30+ dollars. 3D Blu-Rays are not something I particularly need, so I wouldn't even notice the Six Disc's lack of them. I'd appreciate the protected mounting of the discs more than the scratch-prone cardboard sleeves. I'd miss the dossiers, and perhaps some of the extra material included in the set (that I haven't yet delved into), but I wouldn't miss re-purchasing films that become unwatchable due to damage. I also wouldn't miss the absolute disappointment that this Collector's Set has given me with the case and, most of all, the cosmic cube.
I can't tell you if you should buy it or not, because different people have different priorities and opinions. I can only tell you what I would do, and at this point, I have a feeling I'd do things differently, given the opportunity.