There are a couple of minor defects in Ep. IV I've noticed - the bottom end drops out during the "holding her is dangerous..." line, and some of the Death Star battle is slightly out-of-sync. I heard no such problems on Ep. V; DG, care to expand on what you mean by "lacking"?
Things I've noticed with the video in Ep V I'm not happy with - the ghosting caused by the dirt concealment processing (present in the source, not much I can do about that) and some issues with the overall colour (or rather, lack of colour).
But I still think if you have a widescreen PAL TV this version is the best one for you. (For now...)