RE: 243 vs 30-06 (case scenario)
Years ago I started out with a pair of matching 700 BDL's one in 22-250 and the other in .270 win.
Have had lots of different stuff in between, as well as larger and smaller.
Those two chamberings though were relied upon for a very long timeand served their functions well.
Now, I've settled on two different chamberings for the same purposes, but can get more versatiliy out of each one.
One is a .243 and the other is a 30-06.
Loaded as I load nowadays, the .243 is what I consider the ultimate whitetail caliber for most ofmy needs, and the '06 is my "big gun".
Loaded right and shot well, the .243 will doa lot.