I do not think that my expressing an opinion or offering my 40+ years of experience with flail mowers in operating and maintaining them is of little use of little benefit to anyone that asks about them.
The simple fact that I own a smaller flail mower now compared to the JD25A that I used at my fathers place is of no consequence as the principles of operation for any flail mower are the same; no matter whether it is a forestry mower with conical knives or simple bolted carbide teeth mounted on the rotor knife mount or what the rated gearbox horsepower, blade type, hydraulic or belt drive, front or rear mount, width of flail mower, whether its a flail crop harvester with a cross auger to convey the clippings to the internal blower that fills the silage wagon, its useable cutting height or whether it is a orchard and vineyard shredder used to clean orchard rows of limbs and pruning debris or vineyard pruning's or whether it is used to mow down corn stubble, sugar cane stubble, cotton stubble, sugar beet tops prior to harvest, pineapple slash after harvest and many other crops.
I am fortunate to have friends here on the forum to whom I offered advice and have taken my advice and had wonderful results with their purchase and use of a flail mower and I have given anyone who asks advice and help with their flail mowers when they need it to help with a repair or tracking down the correct V belt or any other parts.
It is truly my loss if you feel that I know nothing about flail mowers, simply because the operating principal of the smallest 24 inch push flail mower, the 48 inch Caroni flail mower or the largest 20 foot cut Hiniker flail crop shredder or a hydraulic track driven self propelled Fecon Forestry Mulcher are still the same almost 60 years later after Mr. Mott patented his first flail mower.