Well it was a hunch I got. But "Hunch" is my middle name, what can I say, I'm an INFJ.
I know an ESTJ well, one of my dance practice partners. I have practiced with her for a year and a half now. She hasn't taken the test but maybe I will ask her to do it. I would be very very surprised if she gets a result other than ESTJ.
1. She is very extraverted. (E)
2. Efficiency is definitely her most striking personal trait. (Te)
3. She has absolutely no Ni. (Si)
We don't have a lot in common at all, and even though we have met about twice a week for a long time now, no friendship have developed. Exchanging favours is a purely practical matter for her and not something she does because she wants to be nice. She sees no use whatsoever in dancing with someone that is not as skilled as her. Great practice partner though.
I have also worked with an ESTJ (also unconfirmed) for about a half a year very recently. She said straight out that she is selfish and that she thinks that all people are basically selfish but some people are better at hiding it than others. (I can see her angle, but I would say the matter is a little more complex than that.)
To summarize my experience of (assumed) ESTJs - they are very efficient, very selfish and do not care about people if they have nothing to gain from them in return. (And even then, it is not the person they care for, but the return.)
This may seem harsh, but I also think it is important to remember that "you can't blaim wolf for being wolf." In next life I could be an ESTJ.