Yes, I have used this procedure for small parts while restoring my 67 Duetto. Yes, I was pleased with the results.
From a Chemestry point of view, you are breaking apart the iron oxide molecules. For a more detailed description that is easy to read, check out
http://antique-engines.com/electrol-details.asp
A few critical points about removing rust via electrolisys.
This process gives off hydrogen gas. DO THIS OUTSIDE... NO SMOKING, FLAMES OR SPARKS..
Also, it is critical that you hook up the battery charger properly. The negative goes to the part you are trying to remove rust from. the positive goes on the metal that is attracting rust. Get it backward and you have somethig that is even more rusty...
The final thing is that this is line of sight. This means that there has to be a direct path to the metal attracting rust. See the article
http://antique-engines.com/electrol.asp on how to set it up. This means you must turn the part over to get the rust off the other side. It does not work like a chemical bath.
Good Luck
Oh, one good thing about removing rust this way is that the resultant water is fairly benign. The washing soda isn't very strong and there is rust in the water. Check your local laws, but you shold be able to pour it down the drain when you are finished.