I am new here, but I have websites for my other business, one the products are in grid form, one in list form, the third however is a mix of both. I find that the list and grid sites have very similar sales the mixed one gets very few sales. All 3 are either the first or second page of google search for the same keywords.
I hope this might giver you a clue even though it is in a totally different nitche to this.