Concerning BT Virus Protect and Compatibility issues with MacOS High Sierra. Since updating my computer to High Sierra the BT McAfee software has lost the ability to perform custom scans in individual files and folders. Custom scan still exists but now it is only able to scan the entire system instead of individually downloaded files.
But the BT McAfee is for the mac too. It's just that the latest Mac upgrade has partially broken it. What's needed is a patch from McAfee via BT.
The McAfee product seems to be as much of a resource hog on Macs as it is on Windows PCs, going by online user comments. However it's up to you if you want to wait for an update for the McAfee product. Avast is said to have a much smaller footprint.
I've never had a problem with BT Virus Protect/McAfee hogging resources. It has always worked perfectly. Are you a product placement guy for Avast?
Was looking around for other free ones for the Mac. You may also want to look at Sophos Anti-Virus. AVG is available too, but it's a known resource hog.
Since upgrading to High Sierra I find my iMac crashes and reboots whilst it is 'sleeping'- this results in an error message when I do wake it up. I'll see how it goes for a few days but I may well dump BT antivirus
The problem I originally posted about here is one which now regularly fixes itself after rebooting. Panic over.