Z-spray units: Positives = nice weed contol and product duribility. Good guys! Problem: it's a zero-turn. Requires two hands to steer and not able to operate deflector shield or shut off spray, etc while keeping two hands on the controls. Perma Green units: Positives = easy to manuever. fun to drive. Problems = poor small-leaf weed control, constant corroded wiring, many parts shelling out, deflector shield prevents putting product along curbs for crabgrass control. Both companies have very fine people who answer the phone. Problem I find is the "actual unit".... There has to be a solution. I'm thinking I might use the PG unit & re-engineering it. Changing the battery set up, tweaking the deflkctor shield, etc.? I have ideas such as a motorcycle battery + eliminate the 90 degree fittings .. 90 degree resricts flow--dumb idea in the first place. Currently we have two PG Ultras. One sprays poorly and does not spread (worn out coupler). The other does not spray or spread (broken coupler and ?). Both are 4 years old. Seems to me, expensive lawn care equipment should last longer than a "throw-away vacuum cleaner". Our PG units have been broke down about twelve times over the past 4 years, (cost us money and customers). Right now, I don't know where to turn. Please help. Thanks. p.s. " "senior members" who only respond with selfish critism of members are not appreciated by me. Thanks to all. I totally respect ALL feedback. Those who criticioze the fact that the same subject has already been posted (no matter what subject) really DICUSTS me. Some of you are "senior" members??? Shame on you.