I had a demo this year, although it was the first time I’d demoed anything since the late 80s/early 90s. I’d driven down to Preston to buy a very well priced ex-demo amp from AudioT, but when I got there - rather than have the amp boxed and ready to take my money, they’d set it up in the demo room so that I could have a listen before buying. I find demoing equipment fairly pointless, which is why I’d have been happy not to, but they’d gone to the trouble, so why not?
To be honest...even though they had the same speakers as I use at home, the amp sounded awful. Bright, ‘scratchy’ just horrible, although incredibly detailed. But I knew (or at least, suspected/hoped) that these edgy ear-bleeding qualities would be softened in my home setup, which is a very different environment than the demo room. So I bought the amp anyway.
Luckily, I was right. In my home setup it was glorious - detailed, full, rich. Really lovely.
I think demo’s should be done at home - and ideally, you need to live with something for a while to really know if it suits the room and other equipment.