What distance are you shooting and do you reload ? More bullet selection in 30 cal. I shoot both those cals. I like how flat the 25 shoots but the 308 would work better in the woods IMO. Both are good calibers. If its a TC buy both bbls Problem solved.
It also depends on what other rifle/cartridge combinations you currently own. For me the decision to get a 25-06 was easy since I already have a 30-06, the hard part was finding the rifle. I could have easily chosen another cartridge like 243, 7mm-08, or even the 270. I did some research on the different cartridges and the 25-06 just seemed to "fit" for my intensions.
The 25-06 shows it's true potential in longer barrels (at least 24 inches). The bolt action rifles I was interested in only came with 22 and 23 inch barrels. I chose the T/C Encore with the 26 inch heavy barrel and topped it with a Sightron SII 3x9x42 scope. The fit and feel of this rifle is amazing, it's accurate and is a pleasure to shoot.
I handload using 117 gr Sierra Gameking bullets and Reloader 22 powder.