I havent used 3rd party antivirus for more than 7 years. Common sense and Windows essential/defender is good enough. Havent seen a virus in more than 10 years.
I usually find the paid version is a waste of money. It offers a lot of useless features. The nice features like in Avast you still have to buy separate from the paid version
The 30 day trials do exactly the same thing as the full paid version until the time expires. The best antivirus is Bitdefender. There's no excuse not to have a paid antivirus today as you can get them for free after rebates or for less than $10 per PC per year when it's on sale. I have 7 computers and have Bitdefender Total Security or Internet Security on every device.
Haven't used anti virus since 98 or so, if you use common logic and don't click dumb shit or download from an unknown source you should be good, never had an issue with viruses.