Orchestral music works in some settings, and not so well in other settings.
I starting "finding" the soundtrack for HL2, and it's surprisingly untechno IMO. Many of the tracks I remember from Ravenholm and the final chapter of the game, and brought back some good memories. There are some more techno tracks, but I don't recall the music ever being inapprorpiate for the scene.
If I find many more tracks, I'll probably find myself playing the game again.