Gray Fox,
Though I have settled on the 225 TSX for my Whelen this fall, the 225 NAB shot very well during load work-ups, and I started a thread here to get input from people who had killed elk with the 225 NAB. Might help you.
Who has killed Elk with the Nosler 225 Accubond?
I started an identical thread on the Shooter's Forum to get more opinions - you might read that one too:
Same subject, different forum

Probably no wrong answer, as others have said,
Rex