I have about a 5.75 acre lawn with a lot of trees and consequently a lot of leaves. I have a walk behind Billy Goat lawn vac, which works well but is not enough. Can anyone give me some advice for some lawn vacs that attach to my riding mower? I have a 61" Ferris Z, so that rules out a lot of models. The Cyclone Rake can be pulled behind a Z and seems reasonably priced. Comments and advice are appreciated.