First things first, I played this in 2014, got tired, finished in 2015. I also played first time when it came out, original edition, not BFG. Back then graphics were somehow awesome, but in 2015 it feels outdated (what a wonder :D).
I loved Doom I and II and Doom 3 was a move I did not like. They changed they design completly so in my Opinion this game could be called "Boring Monster Slasher", "I need to reload", "Oh crap, you got me this time" or anything else but not quite Doom. Walking through this game was nice at first but gets old quite fast. Open door, step back, kill the monster, reload, wait for another 1-2 monsters, reload, open next door.
Get it on sale and get Doom I and II with it, which is quite nice. So Doom 3 is not awefully bad, but not that great to recommend it