We played with them when my dad was alive. He even bought semi loads out of sw iowa....fora while.
Cannot recall a time when we saw definitive yield differences.
You have to really break down the testing and the claims.
They survive on rumors of benefit. Most famers will not do "focused" research. actual test plotting in defined terms.
and...... Most farmers will not critically analyze their research.
I always convert the analysis to dollar cost comparatives. example if the benefit of adding $4 of special T is an improvement in yield, then run a third competitive with $4 of additional commercial nitrogen. If special T doesn't out yield commercial fertilizer, dollar for dollar, when added then it's cost benefit is not there.
the research might still convince you that you could benefit from additional fertilizer or just be trading dollars.
Often the high yield comparatives are just that 240 bu corn might beat 300 bu corn on a net income per acre basis. That is extreme but it makes the point.
Seed yield results need similar analysis. Winning field trials is meaningless if the same companys varieties dominate the large share of the trials.
I lost a seed dealeship once because I put too many competitors varieties in the plot.
The company reps understand how to load results better than we understand how to analyze them.
