What do you guys think is the smoothest riding commercial ZT over bumpy and rough terrain in the 48-52" range? I like the Gravely 148Z and the JD717, but I'm concerned about the ride. I know Ferris IS1000Z has a front suspension, but no rear until the 1500Z comes out. Is it worth waiting for the 1500Z or does the front-only suspension make a difference? Any others? Thanks in advance.