Even though they're a pain in the arse to sharpen, I still prefer the big Grizzlys. Once you get the bevel set, they aren't bad to touch up. No worse than any other head.
There's something to be said for the reported benefits of the Grizzlys, especially with a lighter setup, or in the case of a bad hit. Much of it comes in the form of increased confidence in your gear. While most any broadhead on the market is capable of killing any North American game animal, the Grizzlys give me a bit more confidence that I will be able to recover an animal in the case of a marginal or poor hit.
On the other hand, there is nothing wrong with Zwickeys. I've used plenty of them over the years. In fact, I had 4 Deltas in my quiver this past fall. They're easy to sharpen, and I'm sure they've been responsible for the early demise of more North American game animals than any other broadhead.