Will the WinTV 150 really be better than the ATI TV Wonder 200?
Yes. I have upgraded a year ago from a Wonder 200 model (made by Sapphire) to a Hauppauge PVR-150 and couldn't believe the difference in image quality. Also, the hardware encoding in the PVR-150 helps a lot when the computer is slow because there are no dropped frames.
I also tried a Theater 650 product from ATI. The hardware seems good, the reviews are excellent, but the software that came with the card was completely useless so I returned the whole thing.