Just to put my thoughts in:
Having done a training course I found that it confidence inspiring that both instructors were on HT's (Emma and Tracey @ the Hub FWIW). The majority of participants were on FS's and knowing that an obstacle can be ridden on an HT provided a great demonstration of what is possible. Taking the onus away from the equipment and putting it on the technique.
A lot of people will feel (or at least try to justify to themselves) that they need to improve their kit to improve their riding and seeing someone demonstrate what is possible on an HT will help them to realise what the bike is capable of doing, if the rider has the confidence to attempt it.
I love the fact that there's a group of guides in the Alps (trailaddiction?) who use HT's for their guiding, a great demonstration that its not what you ride its how you ride.
If I went on a training course I would take a great interest in what the instructor was riding, partly to see what kit he/she rated, but also to see what a rider more skillful than I felt was necessary to ride what was going to be attempted that day. At the course I attended at the Hub I was on my HT and had been nervously looking at the 5 & 6in FS's that the other participants were riding, wondering what I was letting myself in for, and was very relieved when Emma and Tracey bot turned up on HT's.
If its a bike for work you are thinking about I would take into account what impression is going to give to your course participants.
Apologies for the essay 🙂