Yeah it looks pretty ghastly and shite - thats a Morlot, they used to come with mags you had to load like an AK by racking them forward and then back but thats the new one where the mags load like an AR by pushing straight up into the gun - Open class shooters, especially in Europe - Germany / Russia mainly use them. I think Morlot sponsor the Russian Open team.
I hate them personally, and everyone screws around with them like the one in the photo to make them better / faster / cooler - we tend not to use them in the UK, simply because Open class is not that popular over here.