You can't automate the whole process in Subler in as simple a way as you can with iVI (Pro). The ?10 for iVI is a bargain given that you can install it on up to 5 computers. In any case while Subler is very good, I just feel it is not up to the capabilities as iVI or iFlicks. iFlicks has a very interesting option that will allow a remux of xvid in an avi container into an m4v container. Works great for me.
Philip