I dont have a official ex system but i recently connected a pretty good pro-logic preamp processor to the suround outputs of my dolby digital/ DTS processor in a ex fashion, and while its not a huge advancement over strait 5.1 it has some awsome effects, and Unless your looking to spend only around 500 dollars on a processor getting a new processor or reciever with ex capability will not set you back any more money. If you dont like the ex effect you can just turn it of and use conventional 5.1
