As you can see in the several threads on this subject, there are opinions both for and against the use of ATF. Each poster will have his/her mind set on what they feel are pluses and minuses of using a certain lube in certain areas. The ATF users feel its not a problem, because of what they believe are proven uses of ATF in other applications that are more severe in use than a primary, and for other reasons as well, and the non-ATF users, who feel the lubricity and such is not there, or wont completely lube or lube properly, and for other reasons.
I personally use ATF, and disagree with others on its non-use in a primary, but thats just me. What you must do is evaluate what you read, what you believe, the advice of both users, non users, and their experiences, good or bad, and make an informative decision on that basis. IMHO, No one is qualified to make a recommendation on any type of fluid for your primary except the HD motor company, after all, they built it. Whatever fluid you end up using, I wish you luck with it, be it your current product use, what HD recommends, or the ATF.