Touch Cover: I'm a touch typist. My fingers instinctively fly by feel over a keyboard, if not always at the fastest clip. Furthermore, I don't pound the keys; my touch is more middle-of-the road. For these reasons, my time with the Touch Cover proved to be a mixed experience. I had no issue with the key placement or finding my position on the keyboard--in spite of the flat, pressure-sensitive keys and the ever-so-minute key definition. However, I did tend to skip letters. Frequently. The more I typed, the more it became clear that I wasn't pressing firmly enough.
I found that my accuracy improved over the short time I used the Touch Cover, as I learned to slow down my typing speed, and to vary my pressure to increase the likelihood that I actually struck the keys. That said, I also felt my hands tire more quickly than they would on a physical keyboard. I felt the fatigue even as I dragged my finger over the integrated touchpad, which is made of the same textured material as the rest of the keyboard case. My typing speed reflected the need to adjust: My first take on the Touch Cover was 32 wpm, with one mistake, but when I really concentrated on the pressure I applied to the keys, I came in at 49 wpm.
Touch Cover result: 49 wpm
Type Cover: My experience with the Type Cover was just the opposite. Everything about this keyboard lends itself to touch typing. The surface of the keyboard is a soft-touch, rubberized paint that my fingers could just glide over. And the keys felt well defined. I wasn't error-free on this keyboard, either, but my accuracy was better from the get-go thanks to the physical hardware's feedback.
More important, I found that I didn't need to be conscious of the pressure I applied to strike the keys. Nor did my hands tire as quickly as with the Touch Cover. I also preferred the touchpad on the Type Cover: The smooth surface made navigation seamless, as did the physical feedback from the touchpad's left and right mouse buttons (integrated into the bottom of the touchpad, clickpad-style).
My one gripe: The keyboard itself flexed as I typed, particularly in the center part. Still, for my dollar, I'd pay the little bit extra and go for the Type Cover. The difference, for me, was just that tangible. And my typing speed was more comparable to what I achieved on my desktop.
Type Cover result: 57 wpm