1) As a Professional, "you "know"??? 2) Number of holes = customers don't care or are they are uninformed??? 3) You mention my personal name on this site. Professional??? 4) You got a beef with TURFCO??? Why? 5) Does TURFCO build a stand-on aerator? If so, please let me know. The above "1 -- 5" make you look like ___________ Try this: http://www.ipm.iastate.edu/ipm/hortnews/2005/6-22/lawnaeration.html I certainly do not mean to personally attack you, but I disagree with you. Nothing personal whatsoever. And suggesting 20 - 40 plugs per square foot might be overkill in many situations (unless you're talkin' serious renovation). NOTE: Our Ryan 48" tow-behind aerators come with a "set number of tines", yet Ryan allows one to "double that number" of tines on these aerators. Plugr walk- behinds pull more plugs than you are recommending, and they are great aerators. p.s. "whether" is not spelled "weather". just sayin'