I am in the marked for a ZTR to cut my 3 acres. Don't need anything monstrous, currently cut with t 6 year old craftsman tractor 54" 24hp briggs. Takes about 1hr 40 min. All pretty wide open. I am very interested in the Ferris Is500z. Looks like a great machine, sans the briggs motor everyone bags on. Current briggs intek motor has 200+ hours and has been flawless so far. Was also looking at Toro, Gravely and yes bad boy. Trying to stay south of $6,000 and don't really want used. I see the difference in drive system between Ferris and these others listed. Ferris has the separate pumps and wheel moters where everyone else has the integrated like the hydro pump 3100 or something similar. Which is a better system?