I did like the design concept for both, but I am not certain I would get either as it does add quite some weight and bulk to the iPad2 which, to me, defeats the purpose of being thinner, lighter than the original iPad.
Agreed - if someone designs a case for iPad 2 and doesn't include the rear camera port, that's an instant design fail for me. It diminishes the device's functionality, and making the user remove the device each time just to use the camera increases the opportunity of accidents and damage.
If you're considering a Moleskine-style book-bound case, the style of the case
will add to the bulk and weight of the overall package. These cases are designed for more style and protection, rather than weight-saving or sleekness. A book-bound case will add about 400g, so with the iPad's 600g weight, it adds up to an even 1kg.
Personally, as a very satisfied user, I would recommend Treegloo as their workmanship, customization options and material are generally of a superior quality. As you mentioned, Pad and Quill also offer a similar case (the Octavo for iPad 2) but they use "bonded leather", which to me is a cheaper (and inferior) material to the high-grade vinyl texture used by Treegloo. (cf.
Bonded leather - Wikipedia, the free encyclopedia)
As for DodoCase, it has had a long series of problems with the durability of its frames and corner pads, which results in devices falling out of their frames (Google for "DodoCase iPad falls out" and watch the videos.) That, plus no rear camera port, of course.