I want to download the entire season of my favor tv shows (most are what 50 or 55 minute long) from the Google Play Movies & Tv. I just dont know how many episodes/series I could get on a 64gb sd card? How many for a series that consist of 20hrs of high def? How many sd cards will I need? Is there a particular brand to use for this purpose? It's cheaper than paying $89 complete set on dvds..when you can download for $32. By the way I forgot, I have a Samsung tab 4 and the max sd card allowed is 64g I think.