That white paper we published really sparked some discussion, but it is now to the point where experts arguing with experts is only interesting to the arguing experts. So, I’m stepping back from the fray. This is my parting advice as posted as a comment at Emerson Process Experts:
I guess we could continue “correcting” each other indefinitely, but we are not going to change each other’s minds. Instead, I would encourage potential users of a fieldbus to do their own research and test the technologies on their own as you suggest. There is a lot of misinformation out there, so weigh the evidence carefully and consider the source of the information. So start with each organization’s website – www.fieldbus.org for FF and www.us.profibus.com for PROFIBUS. We are confident that when compared side by side, end users will find that for most applications, PROFIBUS offers better value. But in the end, it’s up to the users.