I always check what is streaming first, to see if there's anything of interest that I haven't caught yet. I think they do a pretty good job with their selection of movies.

If I've seen everything, or nothing is of interest... I always have a few items downloaded as backup.

I know when I'm flying home from my 4th of July trip I will download and watch as much Stranger Things season 3 as I can get through on the 4h 25m flight