Weight is one of the most important factors when it comes to choosing a grapple. Besides needing a lightweight grapple to preserve your tractor's lift capacity, strength is also very important.
To achieve all of the above, we've upped the bar when it comes to compact tractor grapples by using premium, high strength materials to create the IDEAL grapple for many different tractors.
Our Wicked 55 grapple rake is the best match for a 2850 if you want your tractor to have the most ability. At 200 pounds, with extremely strong AR400 tine construction and other features such as upper and lower serrations for gripping/ripping and lower removable runners, nothing on the market comes remotely close. Ted tested it on our L6060(60 horsepower) and put the footage out there for everyone, so we know it's incredibly strong!
I have a Land Pride heavy duty root & rock grapple. SGC1560 at 820 pounds and 63.5" wide. The grapple is used almost 100% to move large rocks and chunks of my Ponderosa pine trees. I also use the upper jaw for backdragging to level and smooth dirt. I have little to no brush here on my property.
The difference between a 60" grapple or a 66" grapple will only be in the added weight carried by your FEL. As far as work that can or can not be accomplished with one or the other- there will be only the weight difference.
This guy chose to go the cheaper route to save some money, but quickly learned he made a huge mistake.
The day it was delivered, he called me and ordered his Wicked Grapple! He said lifting the grapple alone felt like a bucket full of gravel and it got worse when he tried to maneuver it because the tractor's agility was totally gone.
John Deere 4310, which has a comparable lift capacity to the OP's tractor.
Thanks for the responses. I should have said "I will be building one" in the first post. I can't justify that kind of money on one and I have a guy with a plasma table that will cut out what I need and I also have a large plasma cutter if I want to trace some templates. That wicked grapple looks real nice and I like it's weight.