I had the dealer install an Add-a-grapple to my 4720 with 400CX loader (and HD construction bucket with bolt-on tooth bar), and I love it. It does not get in the way when you want to do loader work, and it's always there when you want to pick something up. It saved me from buying a dedicated grapple.
As an example, last weekend, I dug out a 28" pine stump, worked the dirt off with the teeth, pushed it up out of the hole, then picked it up with the grapple. The stump was very close to my lifting capacity, yet I had no trouble grabbing it, and lifting it just high enough to transport it to my brush pile.
I may add a light materials bucket to my arsenal that I can interchange (I have the quick attach setup) for general loader work, since the bucket-grapple combo is quite heavy. By the way, I did load my rears, and that is a must if you want to get the most out of a grapple.
I'm not sure about the cost, since I built it into the original tractor deal, but I sure do like the setup, and I'm sure it's not as pricey as a dedicated grapple.
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