I think Kaspersky still has free 30 day trials, or so this list of free trial versions of AVs at antivirus4u shows:
Best Antivirus 2016 Free Download/Trial version
I did trial Webroot for about a week before buying it so have been using it for about 2 weeks now as my main protection, sometimes by itself, sometimes with Malwarebytes AntiExploit Free and lately with HitmanPro.alert 30 day trial. I also run Emsisoft Emergency kit, Herdprotect, MBAM Pro (on demand scanning only, I want to see how Webroot's auto-protection fares alone) to make sure stuff isn't creeping in. I have found videobull.to a great testing ground for AV and AM products, those links through adf.ly are brutal for trying to inject crap.
I used to swear by Eset AV, and still think it's a great product (robust, light on the system and dependable), but at one point I built a new PC for my wife and no matter what I tried Eset gave me startup problems where the machine would hang. Format/reinstall several times and messed around with it for months before finally just giving up and removing Eset and running AVG/Avast free until I just settled with MSE. This was a Windows 7 64 bit box until yesterday (now 10). It was only after reading around this forum that MSE was not that helpful I started exploring alternatives again and gave Webroot a shot.
Long-winded story but the moral is always try an AV or AM product for free if you can, as it may run perfectly for everyone except YOU.
I'd still be running Eset on my machine (had no problems) but ti's easier for me to keep both machines similarly configured so that it's easier for me to maintain. She's a happy clicker and I love that about her. She's learned to never open an .exe file, but they can be so devious about hiding them and that's just the simplest security problem right there. I also have my 77 year old father running Eset Smart Security for probably the last decade because it works for him and I don't get phone calls every few months asking why he's getting messages popping up to send money to Russia/China/India/wherever to fix his computer =)
Personally (and for now - things change) I think I have settled on Webroot supplemented by Malwarebytes Antiexploit Free and Adguard for windows (can't say enough good things about that software now). I want simple, fast and unobtrusive protection that I can double-check every week or two with a MBAM Pro/EEK scan to be reasonably sure that nothing is slipping in.
If I see Kaspersky for a really good deal (available to Canadians, most US deals don't work) I might give it a shot, but I am pretty happy with Webroot right now after opting out of their autorenewal scheme.