Maybe the answer in todays world is that Bryston have a couple of each model that could be designated as demo items.
So, if a prospective buyer were interested in possibly, say, buying a set of 7BSSTs at approximately $8,000 and had a local dealer (who normally wouldn't stock the item since they likely don't move many 7BSSTs!), the dealer could bring the amps in (at the buyers cost for shipping) and a prospective buyer could take them home and audition them.
This would not be practical, for say, small stuff, but $8,000 to $10,000 items, I'd definitely pay the marginal shipping cost to at least try the amps out. The cost of shipping compared to the price of the amps makes it worthwhile for me, at least, to pay to see if the product is for me. I mean, some people would think I was nuts to not test drive a car before I bought it.....
Again, this is only done through the dealer network. The dealer assesses whether or not it would allow a potential based on how it does for loaning out it's own inventory. As far as security, no gear goes out without a credit card pre-swiped for the value of the amps for security, etc....
This may or may not work....however, for high $$ value gear that potential buyers may or may not have access through via their local dealers if one has to wait for them to put the stuff in inventory, it may represent a practical way that a serious potential purchaser could spend a few $$ to see if the gear fits.
I mean, at some point gear is sent around the world for review purposes...why not have similar gear (it doesn't have to be many units, or even a unit of each) that dealers can ship in and out for demo purposes.
It would likely be only the non-stocking dealers who would have to do this and a customer willing to pay $100 to $150 to ship an amp back and forth is likely somewhat serious about a purchase too.
Hmmmm..maybe I have asked my own dealer about this possibility in the past

Keith