Summary (my opinion)
Ex Brit is moderator from McAfee forums. Possibly is biased, please do your own homework when following his or my advice. He claims that Norton has the same problem. That information was NEVER confirmed. MSE, Avast do not and never did have that problem confirmed. AVG as far as I know fixed that problem months ago. He also claims "incorrect coding on iTunes designers part". I am not familiar with coding, but not new to IT, to know that it is impossible to bypass Antivirus (that is it's whole purpose). You (as computer user) do not want to depend in your life on any one single software product and if you do - you set yourself up.
Once again - equation is simple - there is no alternative to Itunes there are hundreds of Antiviruses. Some of AV solutions are BETTER for Windows consumer users and free. Recommendations MSE and AVAST. I have also read on that thread, that McAfee provided refund to one of the users here. At the very least refund request will make them pay attention to you and that particular problem, that is if someone is a masochist enough to stick.
My personal and biased (I feel that bias is for the right reason) opinion is that McAfee is not targeted for consumer market. It registers to many false positives. In my line of work I recommend uninstalling that program and in 100% cases it fixes multiple problems.