I used warriorplus… well… because everyone else uses warriorplus on the Warriorforum so people are used to it. The checkout process is simple and there are more affiliates already in there (not that any have promoted for me…. yet).
If this product was outside of warrior forum I would use DigiResults. All of my other products are on DigiResults.
I never use Amazon S3 partly because it took to long for me to figure out how to use it ( I am all about speed) and youtube hosts for free. Even for audio files I have used Archive.org for hosting too. 2 things I like: Free and Fast