The problem with RT Protection, is that they don't advertise that having more than one causes problems.
Oh I've heard that... Though I do find that certain "full system" scanners take ages (like, a day or two on end) to complete before giving you any
report -- so it can be very difficult to both address the problem that's actually driving you up the wall immediately, and also get your "full" scan to actually complete. It's not merely tempting to pause or cancel and run something faster, but it becomes a matter of practicality. The question is whether the average user can run something faster and not
encounter a conflict between the various programs when one is paused and the second one is just being installed or given priority to take over and often all under some considerable pressure caused by the malware.
I've also found that some of the realtime scanners are not transparent at all about how to turn the whole
program off. They seem designed more to make sure the user has little chance of actually shutting them down, even intentionally! You may follow what few instructions they give, and the program seems to resist or menus are not forthcoming about just where to actually kill it. Then you think you have turned it off, only to find it's still going in the background with certain "core" functions that were not included in that one very suggestive menu option...