They all are actually made by Laing, and yes, same main "guts", motor, impeller, stuff like that. Only differences are - since some time presoldered tach wire for varios for ones sold by Koolance, motor&impeller only set without top by alphacool. On rare ocasions also different tops (eg. some set with preinstalled bitspower kit or a bit modded stock top (like G1/4 thread cuts)), but it's more commonly seen for DDC clones, not D5 family. You can also solder tach wire to D5 Vario by yourself, if ever wish to.