Been using 270's and Partitions for decades. Trialed Etips & TTSX's a few years ago, great accuracy from both, in multiple 270 Winchesters. Grandsons and I have taken several whitetails with Etips over recent years and regard it as a great on game, as I do the Partition. Happily the POA for both is nearly identical.
I strongly suspect that the ETip might even be a bit better with the added velocity of your mag.
Further, it appears to me that the controlled expansion of the ETip has shown a real reduction in bloodshot meat. So far, no shots through the shoulders, but I think the mono bullets might excel with that placement. I do have experience with Partitions with that placement, and the bloodshot meat is extensive.
First buck I took with an Etip was high thru the neck, ~130 yards, and you could "eat up to the hole". It was a sort of epiphany.
Would also add that I have not had much trouble getting TTSX's or Etips to shoot well out of any of my rifles, a couple of Remington 700s, a CLR, and a Win 70. Start with SAAMI specs for OAL, then adjust, if necessary, for your particular rifle.
