Deus Ex: HR was ok, but I think kind of bland and grossly overrated by the gaming press (which isn't a surprise as video game critics tend to reward polished mediocrity over rougher games that reach further yet don't obtain everything they are reaching for). After playing it and its DLC (which I actually found to be slightly better than the base game, strangely), I have no desire to ever play it again. Compare this to the original Deus Ex, which I've played through 4 times (which, honestly, might be the most I've ever replayed a game entirely through.....I tend not to replay stuff much). So I definitely don't think this DLC is worth 5 dollars, but honestly, I probably wouldn't replay it anyway even if it were free.
Whereas, if Alpha Protocol released a Director's Cut I'd be all over that, free or not. Alpha Protocol is a way way rougher game than HR in terms of gameplay, but its bright spots (writing, its dialogue system, the elaborate intricacy of its C&C and the way in which your choices affect the game in both subtle and not so subtle ways) make up for its flaws and so outshine anything in HR that I personally love Alpha Protocol way more than I could ever like HR. I know its dialgue system is controversial, but it's my personal favorite dialogue system of any modern RPG. It forces you to think in the moment, make snap judgements, and live with the consequences to the point that the dialogue in the game becomes way more exciting than its combat. I replayed Alpha Protocol just for its dialogue system, which I really wish more RPGs would rip off (or at least even just one other RPG. As far as I know, AP is still the only game to do that).