Here's my experience- I have used the 270 and 30/06 for about 50 years for most of my hunting- I have also used the 7/08 and a few other cartridges.
The 243 is the first cartridge that I have used that is a SIGNIFICANT step down from the 06 based cartridges. I have not used the 25 caliber cartridges, (other than the 25/06, which I have used a fair amount)but think that they would be almost as significant step down with just a little more thump.
The 25/06 is merely a 270 that took a week off from working out- what one does, the other can do with about the same effort.
The 243 recoils significantly less, destroys less meat,is cheaper to load for than the 06 based rounds. Ammo and brass is readily available which is important to me. Another factor is that it is available in mny new and used rifles. Another factor is good resale value. I have examined the carcasses of several animals rendered edible by the 100 grain Hornady bullet in the 243 , and based on those wound channels, would not hesitate to poke an elk with one, and certainly not deer.
Another option is to pair a Ballistic Tip and Partition of the same weight and have a great vamint/deer gun in the same package.
Just my experiences
Fred
