Ive got 10 acres that i keep cut regularly, looking into either an MZ 61 with 24hp Kawasaki or the Z 454 with the 22 hp kawasaki. These are the 2 larger mowers in stock at my local dealer with the MZ61 being a residential and the Z454 being commercial grade. The MZ61 has a larger deck and 2hp more than the z454 but the z454 also has a slightly stronger deck and some other more heavy duty features as it is in the commercial category. Does it seem like a better choice to go with the Z454 as far as longevity as it is stated to be commercial? I currently have 2 Poulan 54" 23 hp briggs that just arent working well any more. Thanks for the help