Do you want some real-world experience about the 243 Win and not internet BS?
I don't mean to be flippant, but I shot this outstanding cartridge from the mid 60's until recently. I've taken eastern white tail, groundhogs, foxes and coyotes with this outstanding cartridge. I used factory ammo until I started reloading in the early 70's.
I've owned many various brands of 243's, i.e. Winchester, Remington, Browning, and Tikka. I've tested and shot bullets ranging from 70 to 100 grains.
This rifle shines as a dual-purpose cartridge, i.e., deer and varmints/predators. In today's affluent world, this probably isn't a consideration anymore but in my early days in the sport, most in my area could only afford one rifle. The 243 Win fit the need perfectly.
However, it is also an excellent single use long-range cartridge for varmints and predators. Would I choose it for a high-volume single session varmint cartridge, i.e., p-dog hunting, no. But for deer and varmint/predator hunting applications, you bet.
I never found the 243 to be a "barrel burner" as most gun writers claim. This may be due to my manner of range shooting and hunting. I do not shoot sustained fire sequences which heat up the barrel because this has no real-world applications for me. It's the cold / cool barrel shot that is the money shot for my applications thus that is the way I practice. I've had rifles with 3000+ rounds that still held varmint level accuracy.
Regarding case life, if one controls and monitors F/L sizing with a bump gauge and caliper to produce optimum case fit for a specific rifle, the cases last as long as any other non-magnum cases. In other words, sized properly, case life is not an issue.
The absolute best bullet I ever tested and hunted with in the 243 Win is the 85 Sierra BTHP backed by IMR 4064 or Varget. This is an all-purpose bullet which can be used for deer, varmints and predators. For strictly varmint / predator hunting, the 80 grain Sierra Blitz is outstanding as a long-range option. The 70 Nosler BT is also a very good option. Both back by the same aforementioned powders.
I believe the standard 243 Win case is capable of everything one would want with tailored reloads. If I could own only one hunting rifle for eastern hunting applications, it would be the 243 Win. I base all this statement on my extensive experience with the fine cartridge.