I asked myself if comments made on Dreamstime was helping the overall search results. Then I remember I was having one already made by maybe a buyer during the time DT was asking the designers to left a comment after purchase.
It's this one

It's have never sold elsewhere If I remember correctly and it's my 4th image whit the most views and also have 4 downloads.
I think that comments have at least a small influence on the DT search.
Maybe we can do an experiment like on StockXpert? What do you think?