Its like the ultimate cross between what modern games have and LD halflife, its probably the best Half Life experience I've had. Cross between retro aesthetic and modern attention-to-detail coding.
Word of advice though if I may be so bold to do so, on the hand models, especially the "labcoat" hands, I cannot tell you how much it bothers me how soooo many games ignore a crucial piece of hand anatomy. CS:S was one of the first games I've played that actually cared about this, but
For lack of a better term "Thumb flab" Personally I don't consider human thumbs to be fingers at all, as they have roots and muscles stemming all the way from the wrist and palm; as such should not be rigged as such. Seeing each model has a separate hand mesh I can only be sure it would be more tedious than difficult perhaps, if all that was changed was a small extrusion of skin to bridge the gap from wrist to thumb so it doesn't look like a noodle. Just a suggestion of course. I imagine a simple mesh edit of a few more vertexes/faces could solve the case.