They did a good job.
I really like that they made a practical headcrab instead of using a god damn horrible looking ripped model tracked to the actor’s head for the thousandth fucking time.
That^
And it actually looked good.
Same for me.
What we need is full HL cinema movie.
they broke rule 1 and 2 of Half life (the protagonist doesn’t speak) but I loved it anyway.
“I used to have a lot to say…” 
The practical effects were really well done. Freeman’s name drop was a little too “Bond” for my tastes, but I definitely want to see more.