I have avex, it worked great and was fast.
I can't remember what site I saw that tested all the one available at the time (granted, it was almost 2 years ago now) and that one was rated far above any others for speed
Magicdvdripper.com is great. They have a free download that you can use so many times. They allow you to choose the format. You can even choose to format it to fit on the Disney MixMax players.