Desura Question

You get them on your desura account to download at will...?

Some games are only available on desura and not steam, so if you want all the games in one place, activate them on Desura :)

Well the humble bundles came with both steam keys as well as desura keys, but some games were desura only, so I say its worth it

You already bought the games so there's no reason not to activate your Desura key. You can try out Desura to see if you like it (Personally I much prefer the way that Desura handles updates to how Steam does it, for example). And even if you don't, at least you get extra way to download your games should something happen to your Steam account.