Longtime 270 user here. One thing I know for sure, a 7mm mag shooting 160s at speed kicks noticeably more than a similarly stocked 270 shooting 150s (or anything else for that matter). Many can shoot both, but there is a noticeable difference! Reducing bullet weight on a 7 mm mag helps in the recoil department but I always felt that the real point of shooting a 7mm mag was in using the heavier bullets.
Just an observation from the sidelines!