I doubt you will get any answers from DV on these questions (tho they often surprise me with the effort they will make). I doubt there is any temperature math going on comparing the tips other than what @Stu might do. This is not a recommendation that Dynavap is making and promoting. This is Dynavap trying to satisfy some customers who, for whatever reason, prefer an earlier iteration of the tip design over what they (DV) have considered to be a progressive move forward. There have been other changes besides eliminating 2 fins and reducing total mass as they try to make a better product. I think it is very kind of DV to do this (make a run of an earlier tip), but I think it is asking alot to ask them to divine answers to exactly how those changes are manifest in a one off version of the tip.