My showing experience is limited as I've only shown in my local club shows to this point. We do use carded AMHR judges though. What I've experienced is that it is solely a judge thing. One judge loves, loves, loves, pintos. It shows in his placements in halter sometimes and definitely in the color classes. Another judge just fell in love with my silver bay during one show last year.
I also know that during the earlier shows in our year, when my silver bay has been clipped and her sorrel color is nearly invisible (she clips to dapple gray), she does not get nearly as well placed in either halter or color.
And finally, I love having people come to our house because seeing the preferences of even non-horse folks is fun. And there's always a very definitive pattern. They either are 100% in love with my two pintos or they think my solid color horses, especially my silver bay, are the bomb. There is rarely anyone who can't decide on any particular one and love them all the same.
Personally, I love my silver bay. And my yearling smutty buckskin has the most unique mix of colors in her coat. My dark "black" horse (who looks more chocolate with bay features), simply glows this time of year and I love it. I love my two pintos too...the 5 yr old has the most adorable face of all of them. Yet, my silver bay just makes me so happy when I look at her.