Yes, me as well, but then for me who has now paid the deposit for three pair of M7s as a dealer is different than a customer.
There are several pairs of M7 shipping and being installed in Asia in December. All of the first M7 customers around the globe have purchased the M7s without first hearing them.
I have probably sold 25+ pairs of large scale speakers in the past to customers prior to them hearing them. It happens all the time. I've never sold a pair of large scale speakers and the customers did not like them. They usually have a pretty good idea about a brand and have a good idea what to expect from listening or owning speakers from the brand they are buying to feel comfortable making their purchase.
Also even if someone hears a speaker at a dealer or at a show, they have an idea what it will sound like in their room, but really the speakers they heard at a show or dealer will sound totally different in their room, especially the bass and with their power, electronics, cables etc.
I never will sell a speaker to a customer before first understanding their room and their system and I have a pretty good idea after buying and installing a few hundred speakers/systems over the last 50 years whether there will be any non-treatable issues.