Just for the sake of argument...

I doubt most sales ladies have tried on ALL the various brands and styles of bras so that they could honestly tell you whether this one was more comfortable or not.

Additionally, everyone's 'girls' are different and unique, so what's good for you may not be what's good for someone else, and vice-versa...

So realistically, a sales person is simply telling you what they think you want to hear, to make the sale.

To be honest, depending upon the purpose for such a purchase (are you looking for a nursing bra or something more va-va-va-voom for a special evening with your man?), it might well be MORE useful to hear a man's opinion of some lingerie rather than a woman's.

Just food for thought...