What is the differences between the Canopus ADVC 100 and 50.

I Read the user comments for both cards and cant decide which one to get.

I know that the 100 outputs to tape and the 50 doesn't, but I won't be outputting to tape anyhow.

I mostly will be using it to bring in video from taped vhs tv shows.
It will all be going to svcd and eventually dvd.

What kind of quality can I expect?