A more recent development has been the reverse flame design where the burner fires into a blind furnace and the combustion gasses double back on themselves.
One disadvantage of some of the ramps is that passengers need to walk a relatively long way up the ramps and then double back to reach the boarding shelters.
Magic stores also have access to a black option, with two gaff cards in place of the typical advertising cards (one is a blank face, the other a double back).