As far as I'm aware (I do not own any EA equipment) they are more designed as a value brand? I do not believe they are equivalent in quality and strength as the Brown cutters. I could be wrong here, but take a good look at the comparisons. The Brown 472 that I own has an open back design, which allows me to back into heavy brush, this is pretty essential to taking down bigger saplings/small trees. The Brown 416 is the updated version of my mower, I consider it a "truly medium duty" mower (Still heavier duty than EA's super-duper-extreme-duty, which is why you can't go by their ratings). Brown (and others) also make what I consider "truly heavy duty" mowers, which includes the Brown 672, which if you are looking for the holy grail of rotary cutters (aside from stepping up to an actual tree cutter) then this is it. It has the reinforced open back design but is still a standard style rotary mower.
Brown 672HD Extra Heavy Duty Brush Cutter with 72" Cut | 145 HP @ 54 RPM | Single Tail Wheel | Brown Manufacturing | 8.633.899
I have bent some of the skirt on my 472 taking down trees and backing into boulders, but I don't think you could bend a 672. This mower is too heavy duty as a one time use piece of equipment, in my opinion.
Here is a quick time lapse video of an 'overgrown' field that I cleared.
Kubota Tractor Reclaiming Fields With Brown 472 Rotary Cutter - YouTube
And a photo for fun...
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The FS560 will cut true 4" diameter trees without losing barely an RPM on the (sharp) blade. I can easily cut 6" a little bit slower. This brushcutter is not to be confused with a circular saw blade on a weedwacker, it's an absolute beast of a brushcutter and can make quick work of small standing trees. I use a carbide blade on mine.
This is a good idea in theory, but it stops there. Aside from the fact that most tractors don't even have the lift capacity to even lift the mulcher off the ground, they also are not even remotely designed to deal with the stresses of a mulcher. It's a good idea that many of us have dreamed of, but it stops there.
The tree cutter's are incredible, and also very dedicated pieces of equipment. I'd love to have one, but my tractor is not big/powerful enough. They are incredibly tough, heavy, and very capable. Check some of the youtube videos of them behind a john deere 5065 which is pretty similar to your PTO hp. It's a lot of mower for your tractor.
What I was originally recommending as a possible 'ultimate' clearing setup for your tractor, is not the Brown Tree Cutter, but the Brown Tree SAW.
TSG-2 Tree Saw with Grapple | Brown Manufacturing | 8.633.899
View attachment 549451
(This is a photo of member "My Gym" Daugherty Turbo Saw. The Brown unit comes with a safety screen.)
The tree saw on the 3 point hitch, and the grapple on the front end loader, would make quick work of taking down the trees and piling them up. The nice thing about the Tree Saw (as opposed to the Tree Cutter) is you can cut the trees flush with the ground (or even slightly below ground level) and it can be used on a much smaller tractor. In addition, you can cut considerably larger trees in a single pass. The problem will be that you are left with stumps, but this will be no different than if you had a mulcher as well.
You have the advantage of having an HST transmission, which makes using any one of these implements many times more efficient.
Do you have any pictures of the land you want to clear? How many acres are you trying to clear? Is it level? Rocky?