Critics and fans generally find it clunky. It uses repeated "stock footage" to pad the runtime and includes rough deleted scenes where the Fremen's eyes are not blue because the post-production effects were never finished.
This version was prepared for television in 1988 without Lynch’s involvement, leading him to remove his name from the credits. Dune - Extended(1984)H265.mp4
Most viewers consider this an interesting curiosity but a "painful experience" that over-explains the plot. Critics and fans generally find it clunky
The "Spicediver" Fan Edit (Dune: The Alternative Edition Redux) Dune - Extended(1984)H265.mp4