The hype around Villeneuve's Dune Part Two prompted me to look up this interesting curiosity on Roku. I wondered what Avforums would have to say about it!
For my part it's a weird viewing experience. The extensive CGI looks straight out of a late 90s video game, but of course we have to understand the limited budget and technological constraints of the time. Some of the Arrakeen Palace shots look pretty good, but the sandworms, flying craft and explosions let the FX down.
There's a decent cast but their acting leaves a lot to be desired. Leto's desert meeting with his father, the latter masquerading as "The Preacher", is a rare scene where James McAvoy and Alec Newman manage some emotion and impact amidst generally wooden or hammy delivery by most of the rest of the cast, including some big or big-ish names telephoning in their performances. The model playing Alia can perhaps be excused as English clearly isn't her first language, but strange casting choices like hers underscore the oddness of it all.
At root though the source material here isn't as strong as the original book. Children of Dune lacks a clear antagonist and the midpoint switch of focus from Paul Atreides to his twin children is sudden and jarring. Paul and Leto are apparently worried about the ultimate fate of humanity, but we get too little sense of that and rather a lot of humdrum local plotting. This is a parochial palace intrigue story with too many obscure supporting characters, unclear connections and motivations.