I wouldn't be scared of the blue box Federals. I think they are the 180 HotCore which is usually a fairly tough bullet. If it shoots well for you, keep shooting it. Plus, it'll probably save you a little more money for practicing too. Good luck. Hope you slay one!
I've potted a pile of elk with Hot Cores over 30 years, both in the 270 and 300 WSM. It's a good strong bullet and to be honest, I haven't seen much difference in results from Partitions.