Little experience. According to statistics they very common in population, about 1 out of 10 guys, but somehow I just never really came in contact with them. I think we are too dissimilar or something that our activities/jobs/friends don't overlap much. Or may be I just haven't noticed them or thought that they are boring somehow. Don't know. On their forums they say INFJs are kind of boring to them. According to socionics ESTJ is our best match for long-term relations, so called duality partner. Why these relations are supposedly good is because each partner doesn't emphasize the other's weak point, there is enough dissimilarity to keep interest going, and partners respect each other's strong points.
I have gotten to know one ESTJ over an online game. He is older, in his 40s, married, has a career in IT. He is very Te-ish, likes getting things done, pragmatic, committed to doing his best, reliable, sometimes you see that tertiary Ne peaking through as he schemes and rearranges things when making plans for the future. Nothing too grand. He can also sometimes say some weird things that are not very ESTJ-ish in character and resemble what ENTPs would say, but you can sense that it is not quite on the same level in him as it happens in ENTPs. He is critical of people, especially people underperforming. Strangely enough I can relate to that

Tries manipulating at times, but it comes out very crudely. At least I can see it a mile away, but people still agree with him as he doesn't insist on doing anything usually that wouldn't make sense. He just kind of identifies what seems to concern others and puts it into his plan so that it makes good impression on majority. On rare occasion he has anger outbursts especially if he spots expressions of Fi anywhere. Did I mention he can be very critical of people?
I've gotten into mini-conflicts with him several times, mostly because I wanted to move things along and his approach is to find best position and then fortify in it, entrench, build up a fortress. I just like changing stuff and I can randomly flip from one thing to another. He has made a comment in the past that he doesn't understand how I can randomly change from one subject to another and flip my attention to several things at the same time. He is most comfortable following one thing through and he absorbs information linearly, while I am most comfortable multitasking of course. He gets upset with the ENFP guy because he is very openly random and ESTJ just can't follow the discussion. He understands things in a very concrete specific manner, there is little of this many possibilities, it is very clear cut, a leads to b and nothing else. I'd say this is where we experience misunderstandings the most. Given same thing to read we are prone to understanding it in two different manners.
Some more info here about this kind of pairing - sounds like this was translated from Russian and they didn't hire the best translator:
4th quadra: the rational dual pair
http://www.the16types.info/vbulletin/delta-quadra/16082-estj-infj-duality-description-aushra.html
http://www.typologycentral.com/foru...l-romance-infj-estj-duality-any-thoughts.html