Both calibers are based on a necked down 30-06. A 25-06 115 gr. bullet has a sectional density of .249. A 270 130 gr. bullet has a sectional density of .242. .215 is considered a minimum for white tail deer.
25-06 120 gr. bullet based on an 8 lb rifle has a recoil energy of 12.5. A 270 130 gr bullet based on an 8 lb rifle has the recoil energy of 16.5.
Both cals. have the penetration. The 270 has a higher recoil fired from the same rifle suggesting it will be harder to place a second shot if required.
The 270 would give you the flexibility to buy heavier gr bullets for larger game.