Mike, I am on my 3rd Precision Planting machine thru 15 years and have installed thousands of PP components. I also have many new prospects bringing in KZ or JD meters for inspection/calibration. In spite of those thinner carriers, the KZ fingers, if in good condition, will produce fewer skips with flats than JD. With round seed, the JD do fine and the KZ will sometimes produce a few multiples. As skips are the most costly in a field I do not install any JD parts in any meter.
The thinner KZ finger carriers do well until the finger wear dictates replacing with PP sets. That "scare story" about those KZ carriers is mostly negative hype.
Yes, the PP components are the best performing.
Yes, the PP composite back plate with the adjustable brush is the way to go. With fingers showing wear in any meter, I always replace with a PP finger set.
However, I do not push new PP parts on a customer until the situation warrants (running the meters on the machine is the real test). If new parts are warranted, I always check with the customer first and, after I give him the options, I let him decide how he wants to spend his money.
LA in WI
Check the skip stops for cracking every chance you get. "Nuf said.