I've never owned a 243. I did,however, have a 600Rem in 6mm and loved that little rifle. In my "young and stupid" days I let it go. Never went the "MAGNUM" route, but did try the 30/06. As I have grown older(and hopefully smarter) I have gone to the less oppressive 25's.
250/3000
250 Ackley
257 Roberts
25/06
IMHO, with the right loads thjs battery will fill most of the uses of the 30/06.
GOOD LUCK and GOOD SHOOTING!!!