This has gone from a halachic discussion to one of hashkafa.
Based on the things attributed in the various messages to a number of poskim past and present as well as Roshei Yeshiva past and present it can be pretty much agreed that halachically there is a dispute whether todays electric shavers are considered a taar or not. Independent of that machlokes there appears to be a machlokes as to what constitutes a taar (how it cuts, as opposed to how close it cuts).
Hashkafically too, there is clearly a disagreement (as evidenced by some who cite several yeshivos where a bachur needs permission from a rosh yeshiva to grow his beard).
My personal opinion is, unless you see someone clearly violating halacha by using something which is considered a “Taar” according to all opinions, keep your opinion to yourself. If you are so concerned about his neshama and his yiddishkeit, call his Rav and discuss a plan of action with him.