Got about 1100 hours of playing on HL2DM, as it was my first game on Steam from the free pack, together with HL2:Lost coast.
Got about 400 hours at CSS, 500 at TF2, and about 600 as well at GMOD. I also play other games, such as LoL, my dead Xbox, Minecraft, and whatnot.
I've been in the gaming world for over 6 years now, and playing about 5-7 hours on weekdays, about 7-8 on weekends. Usually gets shorter due to my computer-hatin' dad who keeps yelling me when I'm on the computer a lot -_- Quite frustrating at certain times.
I'm also not going out of the house very often, I mostly play with my friends at multi-player games, we have more fun like that rather than coming to them.