I've done a 30 minute video at 720p on a 2070 super and it took a few days. Also, its going to have trouble with scene changes, as the threshold will be constant for the entire video, and tuning that is going to be pretty hard, and might never catch all the scene changes. Honestly DAIN works better on short segments, with only a few scene changes. It might be worth cutting out your favorite scenes and seeing if you get good results.