RE: .243 or 7mm-08?
I think you will fing that there is not that big of differance between the 30-06 and the 7mm-08. Recoil will be notcieably lighter though. If you are going smaller than 30 cal I would consider a 6.5mm (.264) bore, 6.5x55, .260 or a 25 cal (.257) .25-06 or .257 weatherby mag, .257 roberts, even .250-3000 savage. These will offer better power over the .243.