The freeware version works just fine for me. Just remember to do your smart updates at least twice a week.

Beware of this company.
If you download and install their software, once you pay you have to register and manually prevent them from automatically debiting your account at each renewal (yes, that means they don't need your permission to take your money)

PC Tools AntiVirus is anti-virus software with plain interface. Detection precision does not have any problem, but the scan speed is classified in slow one. I use the load to the memory by the resident protection function of this software too much greatly, and it cannot be said that I am convenient. I think that reduction of the memory load at the time of the resident protection is the greatest problem of this software.