The landlord mows most of his 100 acres of pasture with two 2000 series cubs.
A this time of year it is all Tussock grass and the ground itself used to be horticulture so is drainage ditches every where.
I do a lot of the nastier bits with the up front slasher on my 8 Hp rover ( local OZ made ).
2000 series Cubs seem to be readily available on evilbay & Craigs list very cheap they go for $1000 to $ 2000 down here.
If it is sill available Rosey65 here has a Simplicity with an up front on it he is thinking of selling, exactly what you want.
There are some pictures of it on this thread
http://www.lawnmowerforum.com/build-yourself/28928-home-made-heavy-weed-brush-cutter-3.html