To install it, any other anti-virus software (e.g. ClamXav) must first be completely uninstalled.
I've never found it either necessary or otherwise desirable to install anti-virus software....
....the first two posts here
, even without regard for some of those farther down the page, would be deal-breakers for me...
So, here's my experience. Except for ClamXav I have never left any virus checker installed. I've found they affect the performance of my machine by slowing it down. Sophos was the most serious offender.
I have used Avast, and it was quite simple, although I did not uninstall ClamXav and it was broken afterward. I definitely would not have used Avast if I had been aware of the data mining aspect.
Except for ClamXav, I have got into the habit of only using a virus checker periodically, perhaps once a year. When I do, I install the software, do a complete scan, and then uninstall. However, It has always been a fruitless exercise as the machine is always clean.
So, I'm coming around to Artie's way of thinking and may simply stop altogether. Well, may not altogether....I'll likely always keep ClamXav. And that may only be because I'm a notorious cheapskate and, having contributed to ClamXav more than once, I'm just getting my money's worth.