That's interesting. After reading the threads here on the Caroni flail mowers and flail mowers versus rotary cutters, I had thought that with "fine" cut blades, and not "hammers", the flail would be a better choice to cut pastures into an extended lawn. The field currently gets hay'd periodically, so there aren't hidden dangers, it's just pretty rough and bumpy.
I used to use a woods rotary cutter, and it left wind rows. I'd rather spend an extra hour or two every few weeks to have the cuttings shredded, than to have 7 acres of extended lawn look like freshly cut hay field. Kicker here is that the extended lawn is actually going to have a small green at the far end from the house, to make a 200 yard Par 3 for my wife and dad. It will also have a bunch of fruit trees. (Why not, right).
If it wasn't so much open space, I'd just finish cut it more frequently, but I'm not going to beat myself up with a zero turn or such on 7 acres of rough pasture, and I don't think the MMM which I know we'll get for the 2-3 acres of finished lawn will do well on 2' grass.
Todd