I wouldn't even spend the money on the Silvertips, I'd go even cheaper and shoot the Federal Power-shok. They're the cheapest around, at least around me. Usually 4-5 bucks a box less than Rem. Core lokt or Win.PP and will kill deer just as dead at any range you can hit them, plus they shot better than anything else for me. That was what I shot in my 270 and 243s before I started handloading.
The only one shot with the 270 was at 30 yards head on, hit at the point of the neck and shoulder, it didn't come out but everything from the heart to the liver was jelly.
In the 243 I took deer from 30 to 150 yards with the Federals, went through all of them.
You never know, neither of the two rounds you picked may even shoot decent in your rifle.