I have a pair of ARC's, having previously had Tannoy and B&W speakers. I think it's a combination of things:
1. Relative scarcity of reviews, press and zero advertising / PR and the website could be better : http://www.shahinianacoustics.com/ if you already did'nt know.
2. Looks / the 'ooh' factor - people are more used to seeing 'a box with a speaker driver stuck in it' as Richard Shahinian likes to say, than the squat pryamid-y look of the Shahinian speaker family.
3. Hard for people to get demo's as readily as mainstream makes - I live in the middle of London - one of the worlds biggest cities for godsakes - and still its difficult! Most potential buyers won't do that much legwork.
This ties into the comments made by others about the dealer network or lack thereof and the fact for some reason they simply aren't presented in stores like other speakers are.
I don't think being ' hard to drive' and room placement are issues, when you consider that ALL speakers have various niggles and preferences and Shahinian's are no worse than other makes.
In fact it's that kind of rumour perpetuation that can further harm Shahinian's profile, encouraging prejudice. Professional reviewers have gone so far as to say room placements actually LESS of an issue than conventional speakers, see the reprinted reviews from respected independent hi-end audio magazines on the Shahinian's website for confirmation of my own personal experiences regarding placement etc.
http://shahinianacoustics.com/Reviews.htm
I would really urge any prospective buyer to disregard any 'nay' sayers and think why this brand has survived for so long, with so many devoted fans & simply listen to the Shahinian range.
When compared to the competition, Shahinian's performance & value come out really strong across all their models.
Give 'em a try & then make the call, having decided for yourself.