Cowboydoc is right about there being a broad choice among cutters.
What I want to address is the buttercups. We "had" tremendous amounts of that in with the horses here in the Pacific Northwest. Cutting does not make them go away. LIME. The buttercup like a lot of our weeds love acid soil. Copious amounts of lime. This year as the spring growth came, you could tell where I'd put the lime last year. "Now it will make my decision on a rotary cutter different when I purchase new because there has been such a drastic change to what I want to cut." The horses love it. More random feeding area's . It is still wise to look into a chain harrow for scratching up the pasture at times and kicking round the road apples. Generates new growth and thatches the old.
Short cut for a lawn and tall (3" to 4") for the animals.
"What is a weed? A plant whose virtues have not yet been discovered."
Ralph Waldo Emerson (1803-1882)