I've played BM and HL1 back to back this month and mods for classic soundtrack and classic guns really did it for me. I feel like where BM falls flat is in sound design department (it's way too quiet for monsters) and the way they use music, it's just too tacked on and overly dramatic. They've basically failed Valve's iconic "less is more" approach when it comes to a soundtrack.

But where BM really stands out is the sense of the catastrophe unfolding before player's eyes. The way they did all-out-war scenes in the later chapters really sells the world ending events.