I assembled a PC for home just 5 and half years back and from the beginning I was using quick heal internet security for 2 and half years without any pc infection but when I became a member in this security board, I'm frequently changing my AV like changing the underwear (seeing the discussions in war room and video reviews) one I bought (ESET) and few I tested- Emsisoft for 3 months,Avast for 2 months, (KIS for a week from West Virginia promo) won in contests but settled at eset.
Many of my friends who are not members at any security forums, they are happy with their antivirus whatever they have installed in PC/laptops.
I have used a lot of antivirusses both free and paid , to name a few ; norton is , norton 360 , bitdefender , avg ( both free and paid ) , 360 ts , avast , mse , win 8.1 defender and comodo.....currently using bullguard internet security 2014 ( version 2015 final will a , arrive next month )
I use paid software.I am fortunate enough to have made some friends & affiliations during my online travels who provide me with paid versions of software.
I have only used 3 paid security solutions in well over 15 years
Presently I use EIS 9 on all my Windows 7 Ultimate SP1 installations,which includes a couple dual boot machines.
I switch off right now with new versions of ESET & Kaspersky on all Windows 8.1.1 installations
KIS 2015 on one dual booted Windows 8.1.1 & ESS 8 on the other Windows 8.1.1 installation
I have tried many paid & free versions but these three have kept me infection free for over 15 years.
I am using ESET from version 4. Used Bitdefender and Avast for a while but Bitdefender was too heavy (compared to ESET) and Avast didn't detect so much PUP in installers and didn't impress me overall. Never got infected.