My problem with taking a 5.1 mixed film and watching it in 2.0 is that there is information loss....no doubt about it. You can't possibly watch it without noticing that there is something missing, no matter how great of a 2-channel setup you have. Where is the rest of that infromation going? If it's discrete 5.1 sound than it is getting compressed down into 2 channels or information is just getting lost. Now if the movie contains an option for switching over to 2.0 channels than that's fine with me, but anymore it's usually just 5.1.