Humble Bundle Key or Gift?

But it's easier for you to be believed if it's a gift link rather than a key. And Humble support can also revoke a redeemed key from Steam and yank a claimed gift right out of an account. People do not want to play the lying game with Humble gift links, because they can also get their Humble account banned.

Some game come with steam only so there is only a key but some come with steam and DRM free, so you have a key but you can still download them in you HB acount. I don't think downloading them do any trouble to the key owner. I don't know if you can delete the game tho

You can instert the gift link in the giveaway as a "key", and when you send it, the winner gets the link. ANd yes, links from HB are preferred in trades and are also better in giveaways, as they can be tracked if they were redeemed or not.