There is a recipe in the fatfree archive by Thomas Collins (yes,
really his name.) In the search window, just type the two words, onion
ring, and you can find the recipe. He felt that they tasted as good as
the real ones. One of these days I've got to try the recipe.....
I believe the one piece of feedback I saw was someone who suggested
that you dip the rings in seasoned flour before the egg
substitute. This might be good to try since it could make the egg
substitute adhere better.