In the past, having been in sales for many years, a good piece of advice I was always given was, no matter what, NEVER criticize the competition. If you ever walk in to an A/V store and the sales person is criticizing equipment they don't sell, you turn around and say "adios". I have had instances in the past where the person in the retail outlet was knocking equipment that he didn't know I owned, so in essence he was calling me an "idiot" for owning it.
Of course, they are going to promote the lines they carry, but the above advice is a good rule to go by to determine if the individual has any idea at all what they are talking about and be able to steer you in the right direction.
