[AndrewH]

The T1 doesn't feel flimsy, it just doesn't feel as "rugged" (for lack of a better word) as it's predecessors.

I think the necessity of a case is dependent upon where you're going to use your reader. My old PRS-600 never left the house, and almost never left my bedroom. I was quite happy with the simple neoprene sleeve it came with; though it provided almost zero protection, it kept the dust off when I wasn't reading. My T1, however, travels with me to and from work. I have a hard-sided book-style zipper case that protects it very well, and wouldn't dream of taking my reader anywhere unprotected...

Unlike JSWolf, I find the T1 much more comfortable to hold without any cover. Half the reason I upgraded from the 600 to the T1 was it's so much lighter, though this advantage is negated by the case.