I haven't had any trouble with it. In fact, I had planned to just start wearing my contacts again, but I've found I don't really need to. And I use the VF exclusively, not live view. In all fairness, though, I don't often use the shooting info in the VF, since I usually have all of that set before shooting. When I do use that info in the VF, it is mainly three things: shutter speed, aperture value, and in-focus indicator. And those three are centrally located, so I doubt they are affected by your trouble seeing the corners. As far as framing goes, I haven't had any trouble with that. But everyone is different, so you have to be the judge of whether you are having trouble with it or not.
Before changing cameras, though, make sure the other camera improves in this area. I don't find the K-x's VF much smaller than others I had tried in stores, unless you move up to a larger class of cameras. And then that's a whole different conversation anyway.
Either way, good luck and happy shooting with whatever you settle on.
I am wondering what your experience is after receiving your camera as someone who wears eyeglasses. I have also received my k-x but I find that with my glasses on I cannot see the corners of the frame very well. Is there any adjustment I can do to help? I am seriously considering returning the camera because of this - a shame since the camera works fine otherwise.
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Proud owner of Canon S30, S45, A710, Fuji F31fd
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-- Joe S.
'The laws of nature are but the mathematical thoughts of God.' ~ Euclid