The 1984 "Dune" film by David Lynch is said to have multiple cuts, many of which add back deleted scenes that weren't in the theatrical release. Altogether, I think the "complete" film would be something like 4.5 hours long. I've attempted to find something comparing the different versions available - both on DVD and online/streaming - but I've had limited success. According to the wikipedia article I'm linking to, there has been an "extended cut" released on DVD but nothing official and/or endorsed by Lynch.
What is the most "complete" cut of Lynch's 1984 Dune film that is available?