IMHO, a bucket grapple is one of the most versatile combinations you can have. But like anything else, there will be a lot of opinions on it that may differ than mine.
I thought about buying a dedicated grapple but my fel is not a quick attach type. With the bucket grapples, I've never had to take them off. This was of great importance to me since during my daily chores, I always needed the bucket AND grapples for clearing, moving dirt or rocks, etc.
You can do just about everything with the bucket grapples as you can with a dedicated grapples. Not only that, but it's like a cross between a 4 in 1 bucket and a grapple. Draw back is you get more dirt in the bucket since it's not sifted through like a true grapple that has tines on the bottom. On the other hand, you can't move buckets of dirt with the dedicated grapple as well as with the bucket.
My bucket is 72" so I put 2 on. It can pick up odd shaped objects because the independent jaws close down on the object at different points to hold it securely.
I have a toothbar also so I can pick up large amounts of brush and pop out trees and shrubs with the toothbar/bucket combo. But I think a dedicated grapple would have a larger capacity because they don't have the side lip of the bucket. On the flip side, the side lip also allows me to hold even small diameter logs tightly for sawing since the bucket grapple closes with little gap.
I overcome getting a bunch of dirt while grabbing shrubs and brush by using the "clamshell" method. That is I open the grapples up and fully dump the bucket. Then lower on top of the pile and grab using the true 3rd function WR Long valve that allows both grapple and bucket curl to close simultaneously like a clam shell. This leaves the dirt on the ground.
There are many TBN members who love their grapples and 4 in 1 buckets too. And they are certainly worth it. It would be great to have one of each like a 4 in1 bucket and a dedicated grapple since they each have their strong suit. They are ALL great tools. You'll have to figure out which one would suit your needs best.
But if you can only have one, I'd go with a bucket grapple for the versatility it offers, lower cost and the least amount of switching around. I love mine.