I C Cowboy, the 204 is doing fine & I believe it will continue to do so. It fills a niche, it gives 22-250 type performance, at least in small Varmit situations, & gives good performance in a round that will hold up to volume shooting, as in PD's for example. So, the niche is 223 type volume capabilty with performance more like a bigger 22(at least for smaller Varmits & for some people big varmits too), & with powder consumption more like the 223, a dang good combination.
The Super Shorts offer more problems than solution.
HWD, I saw this many months ago, but Rick Jamison (the gun writer), won a lawsuit against Win. stated that his short mag design
was copied. I did not keep copies of this, just read it and moved on, I am sure you could do a search or prehaps go to shortmags &
read more.