In our area it is hard to beat the 270 Win, 308 Win, 7mm-08 Rem or the 30-06. The 243 Win does pretty good around here too since the deer are pretty small. What kind of varmints are you thinking of hunting? Second question that I forgot about before, do you reload? If not the there would be an advantage to the 243 since you can get 100 grain loads for deer or lighter loads for varmints off the shelf.