$15 is a very fair price for Deus Ex, Deus Ex: Human Revolution Director’s Cut, Just Cause 2, Lara Croft and the Guardian of Light, and Kane & Lynch 2, if you don’t already own them. It’s still not bad even if you do have some. That you’d also get at least a dozen other games, ranging in quality from old Thief (at the high end) to Daikatana (on the low), is just gravy.
Square Enix are flogging 16 or so games cheap in the latest Humble Bundle, coming in three tiers depending on how much you fancy spending. It’s well worth a look.