I see a big need for the Bkout/Whisper in supersonic form.. it has very little muzzleblast and recoil. That translates into an awesome kid deer rifle. In my neck of the woods a lot of people set their kids up with either a .223 or a .243 as their first deer rifle. I do my best to try and sway them the other way.. every time a youngster shows up at my farm with a .223 I know if they shoot..we are in for a long track job. The last one took an hour and a half with a behind the shoulder shot on a big doe.
X39 filled that niche easily for lots of kids around here. AND plinking ammo was cheap....
No way I'd go whisper just for that use, well if I wanted a can on it yes.
If you have to track with a 223 you better rethink bullet choice or shot location. Same with 243. I've had more bang flops with 243 than with ANY other round, including a lot of mags and even ran light and fast in some of them to see if it mattered.
Hour and a half to find a deer means shot location was behind the shoudler, but how far... or piss poor bullet choice.