researching information about mowers/vacuums to mulch and gather leafy debris

In the very near future I will be installing over 3 acres of Paulownia for timber and raw material for anaerobic digesting and that will require a mower and vacuum to gather the debris to easily dump into a digester. The trees will be 10` apart, so there is little problem with space. Is there anyone here that can lend some insight into this operation with some links to visit? I`ve already discovered a few places that sell different versions of what I will need , but would appreciate more information to make a better informed decision as to what quality there is to be found. I realize that there is much out there , but sometimes it is better to see what others experience is along with the availability. Thanks for any help and I am an engineer with hands on experience with agriculture and all that goes with it...