X-Way Forensics practitioners needed
Probably it is just me, and I am nit-picking, but it seems like you are looking for practitioners or academics that have been using the tools for no more than 1 hour. 😮
IMHO, "duration of the interview is expected to be less than 1 hour" would have been less prone to possible misunderstandings.
Now, seriously, and not to put you down, of course, but I don't think that you will find many qualified volunteers, at least among the practitioners, as generally speaking they tend to use this (Autopsy) OR that (X-Ways) tool, and very rarely it can happen that both are used by the same person on the same case.
When it comes to the academics, some of them may be proficient with this AND that tool, BUT they will have used them NOT on real cases but rather in this or that (usually narrow) fake (i.e. created ad hoc) data/device, so while they may provide some sensible opinion on partial, specific uses of the tools, they are very unlike to have a good experience on real life usage.
Anyway, sorry for the side (and pessimistic) note, hope you actually find some qualified people willing to help you.
 I would bet that X-ways Forensics is waaay more used by professionals, at least from what I have seen/read on this board it seems like it is on a different league when compared to Autopsy