I have used both eyetv 250 and miglia TVMax. My experience with both has not been good. I have a TVMax right now, and am having a few problems. The tech support is trying to help me though. so probably it will get sorted out. Hopefully my experience helps you.
I have a 20" intel imac. I had initially bought an eyetv 250. The problem with the unit was that the channel quality was not very good. most channels were decent. however some had a lot of graininess. but the biggest problem was that the closed captioning did not work properly. it used to drop letters in almost every line. It did not display it properly even when used with a dvd player. after a series of mails with the tech support, they realized that it was a problem with my unit and offered to exchange it. However, i asked them for a refund instead and they obliged. (on a side note - elgato customer service is excellent).
then i purchased the miglia tvmax. the quality is excellent. every channel is crystal clear and closed captioning works perfect. however i am having a very annoying problem that occasionaly i get 0KB files on scheduled recordings (the recording counter remains at 0 seconds). it happens at least once every day, and i am not able to find the conditions when it happens. whenever this happens, the tv window displays "this channel is not currently available". it gets stuck at that, and even if you change channels, it displays the same thing. if i close the tv window and reopen it, then it works perfectly. the tech support asked me to reinstall eyetv software, as i had not done a fresh install when i changed from eyetv 250 to tvmax. however, even after a fresh install the problem has not gone away. i seems to me (though i am not sure) that it happens when the computer has been at sleep for many hours. when it wakes the computer, the tuner does not tune as fast to the channel and gets stuck. i updated the case to tech support just this morning and am awaiting their reply.
i shall keep you updated.