Their proposed solution offers more flexibility in that you can use media queries to specify the upper/lower bounds and also specify the filenames. This feels o

Their proposed solution offers more flexibility in that you can use media queries to specify the upper/lower bounds and also specify the filenames. This feels over-engineered though, firstly because the above solution provides enough information to switch between images (we're not changing the layout here) and secondly because a filename convention is adequate for referencing them. The third reason that I dislike their solution is that it introduces presentation logic(media queries) into html.