Does the Ares Viper Slivergun, Fichetti Tiffani Needler, or Remington Roomsweeper gain all the options of flechette shotguns in terms of choke settings? My reading of the rules on using Choke Settings on page 180 seems to indicate no, because it's specifically calling out shotguns. On the other hand p189 on defending from Flechettes doesn't call out shotguns as the source. The other references to choke or flechettes don't indicate. If I load a standard gun with flechettes rounds as per the flechettes ammo rules, it doesn't say I get a choke option. The various non-shotgun weapon descriptions just say they use flechettes, or in the slivergun case, "count as flechettes," but doesn't say they work as like shotguns or that they have choke settings. The Roomsweeper is described as being more like a shotgun, but it doesn't indicate if that gives it choke options.
Am I over thinking this? Do all flechette weapons have choke? Did they have choke in past editions? If I loaded flechettes rounds into a superwarhawk would it get choke settings?