If you don't already know this by now, valve has updated their anti-cheat engine.
Instead of being programmed ahead with codes, and searching for a preset code/string it's now being coded by the vac anti cheat guys on-the-go, aka live-stream coded.
Livestream coded?
This means, the guys who are working on steam activley adds new anti cheat searching strings into the vac all the time wich makes public hacks detectable very easy and very fast!
Just thought this is good info for you who use hacks, i don't but i know the games aren't cheap.
They updated in silence to vac3 on january the 14'th.
If you are already banned bu vac3 it may take up to 3 week's before you are banned from the secure servers.
(Vac ban's per engine basis if you hack in css you will be banned from all the other source engine games)
Heads up!