Flail Mowers With Brush Tractor Attachment: Brush Hog Vs. Flail Mower?

Tractor attachment: Brush Hog vs. Flail Mower? - flail mowers with brush

For 5 + acres of land with only grass and weeds (brushless), which is better, swinging a pig or a brush? I can hear the brush has a better job covering and provides a clean cut.

Any information is appreciated.