The creedmore is really a necked up and improved 22/250 case. Similar cartridges existed as early as the 70's for use in handgun silhouette shooting. IMSHA was a family of cartridges that are within spitting distance of the same shape.,
The main purpose of this cartridge is to get tangible speeds out of the heavy 6.5 VLD bullets and still cycle through the standard 308 mag.
Most mags are short 2.8" or less. This limits seating VLD's in a 260Rem and keep the boattail out of the case volume. The 260 works best with a 2.9 to 3" OAL.
The shorter Creedmore allows the bullets to be seated properly and stay within that 2.8" length. To match the performance of the larger cousin, the pressures are elevated to magnum pressures.
Basically, the creedmore does at high pressures what the 260R does at standard pressures. Ramp up the 260R to the same pressures and you gain about 100fps.
And by the way, the 260R works just fine with the bullets seated 'deep' despite the horror of creating donuts. But is another story.
So the Creedmore is a nice design to fit a particular niche need. It is no more accurate then the many options from the 6.5X47L through to the 6.5 Swede improved. All you are doing is finding a balance of fit and performance.
I think response has been positive as it was promoted properly from the beginning as a factory target rd. Brass is near impossible to get so must think factory ammo is selling briskly. The Americans do like shooting factory ammo.
The voodoo to load for the cartridge was spelled out on the side of each box so handloaders didn't have to fret what to use. Sounds good at first until you realise most competitive shooters are by nature, very experienced reloaders so this info is more marketing then useful.
If you are shooting F class, the cartridge is on the small side and unless you really want to have it, there are much better performing options.
The only area where I can see it gaining any popularity is in US High power and tactical matches where the length of the mag is the limiting factor in the design of cartridge and rifle.
Except for those shooting Savages, Tikkas, the mags are simply too short to be interesting.
For hunters, they will realise what a wonderful and effective cal the 6.5 is. Ironically, they will discover what the Scandinavians have known for over a century and what they should have learnt from the 260Rem a couple of decades back.
Jerry