I have a BK2 and a esee 3 and I guess it depends what you wanna do with it, the BK is heavy, thick and has fat handles. It gets the job done but I would never carry it. The esee is just the opposite and I carry it all the time, probably can't pry a door open with the esee but its nice knowing its on your hip. lots of colored after market scales avalable also.
These knives are in completely different categories, as well as being in different categories from the knives the OP was talking about. The BK2 compares closely to the ESEE 5, and the ESEE 3 is closer to a BK11/14 than anything else you can get from Becker right now. That said, I completely agree that both are great companies, and both have great selections of knives

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@OP
I wouldn't really say that the ESEE 6 is a "large" knife either. So depending on what you are wanting the knife to do, it might not work exactly as you were planning. The ESEE 6 is by no means a bad knife, its just not going to large knife tasks (chopping and battoning is what usually comes up) as well as either of the beckers.
I have the BK2 and the BK9, and quite like them. The BK9 out chops my (crappy) hatchet and is lighter as well. Its a large knife, but I can still do little work fairly well. I don't have the BK7, but that is likely my next one. I think that 7in is pretty much perfect for a belt knife, and would like to test that theory out.
A review of the BK9 I did a while ago.
http://www.bladeforums.com/forums/s...-vs-KaBar-ZK-War-Sword-(PHOTO-HEAVY-and-EPIC)
I personally like the grivory (wish I could get different colors, but thats a different matter), and have never wished for more traction than it already has. Speaking of the handles, I find the Becker handles very comfortable, and with the grivory I can easily use a blade for hours and get no blisters.
The sheath is what it is. It is functional and thats about it. Its not a "bad sheath", but neither is it great.
I guess what I'm trying to say is this: If you're looking for a "large knife" then the only ones that you mentioned that fill the bill are the Beckers. The BK7 and BK9 will out chop and out batton the ESEE 6 by a pretty fair margin. Just comes down to what you are really wanting the knife to do.