If you have a Powermatic e16 in nice condition I'd spend the money on a Byrd head for it. Newer planers are not built like the old ones. The Byrd head will run quieter than the current straight knife. The only thing I didn't like about that series of Powermatic planers was that the motor was mounted outboard. Makes it easier to service but takes up more space in width. They were built like tanks and, if taken care of, will run several lifetimes. I have insert heads on both my jointer and planer, much better than a straight knife. Tearout is a thing of the past and I get about a year and half between knife rotations.

I'm in the camp that doesn't care for the insert heads.

I think the helical heads that get ground in the machine are the best all around. They can leave a very fine finish, and they have enough gullet to hog.

I have a Tersa head in my planer. It's just too easy to swap knives. Not even pushing it takes me 7 minutes.

The chicklet heads do make an awesome chip as far as dust collection goes.
Rotating inserts is a chore.
The finish isn't that great from what I've seen unless you're extremely diligent about cleaning and torquing things properly. Most things go through a widebelt after, so probably not that big of a deal. It just bugs me.
They are quieter, but that's never been that important to me.