Let me preface my comments by saying that I have always liked POW. It may have been the first "great" course I ever played, back in my late teens. Back in the day, I thought it was one of the best courses I'd ever seen. It will always hold a special place in my heart.
HOWEVER, today I have played just about everything of note in Michigan that is worthy of consideration for the Top (however many you want to list). I agree that it's a fair test as well as challenging. But to me, there are too many ordinary holes for it be in the uppermost echelon in the state. For example, #'s 1, 6, 10, 11, 12 (now that the tree is gone), and 13 are solid holes, but I'm not wishing that I could play them over and over again. Overall, there is not a lot of strategic interest to keep me clamoring to have another go at it when I walk off the 18th. From a difficulty standpoint, it's not a pushover yet my last time there I hit it reasonably (decent, but nothing special), yet I didn't miss a fairway and shot a few shots under the course rating. All of these factors together would make it very difficult FOR ME to include it near the top of the heap. It may be interchangeable in the 8 through 12 spots (those are arbitrary numbers, so don't ask me to list my top 12) with some others, but above that I would have a hard time swallowing any justification.
It's definitely worth a visit, but I wouldn't want someone to think that they are going to be awestruck when they walk away from it.
Just my $0.02.
Regards,
Sobe