Personally,
I feel that in the field, so to speak, you probably will not experience much if in fact any difference in performance.
I suggest handling each rifle to determine what is best for you in terms of fit, balance, pointability, etc.
If you really pushed it I would probably say the Tikka gets the advantage due to the SAKO barrel. Again, this is more to bench rest results than in the field where you have many variables such as your own excitement, perhaps a not so optimal shooting position, wind gusts hitting you, moving target, etc.
I am a little surprised about your choice of the .270 for such a large animal. Have you considered some perhaps more game appropriate cartridges? That is not so say the .270 will not do the job - just that I feel it is a little light for the job at hand.
Best wishes.