Excellent guide man. Huge help. Yea I think equipping those keen observer tonics as soon as possible is pretty crucial so that you get as much research done as quickly as possible so you don't miss the cheev. Along with he extended reel too. I found using electric shock 3 and blasting them in the face with the shotty got good scores everytime, and switching to the machine gun every now and then. I always used electric shock though. Those Houdini splicers can be a real pain to keep immobilized.