The FAA feels strongly enough about preventing microbial growth in all FAA operated aircraft that they treat all turbine powered aircraft jet fuel with BioborJF on a regular basis. It's the same stuff I use in my boat and will continue unless and until I hear from a reputable source that it's no longer effective. I don't have as much experience with it in my boat as some others here, but I'm convinced from its use in aircraft I've operated that the stuff does what it claims to do.
I don't add Biobor JF to fuel pretreated with ValvTect additives.
BioborJF