I will wade in with my opinion and my opinion only. Ihave over the past few yrs owned quite a few EKI's. No customs mind you but the production versions. These include the Commander line both large and small, MachI, 3 CQC7's, 2 Ravens, and that little hooked LaGriffe. The LaGriffe imho is the most useless piece of steel yet devised. This was made out of 154cm and for the life of me I couldn't figure out how to even get it remotely sharp.
Handle ergo's are second to none. They just feel good in the average hand.
Chisel grinds:
Dull Chisel grind sucks plain and simple. You can tell me all you want about how the chisel cuts even when dull. Well I don't see it. I have experimented with a Commaner full size cutting various things from rump roasts to trying to cut through a blanket line Carhart work coat. Now take that same knife, reprofile the blade down to a true chisel edge and you have something. Did this on my most recent CQC7, but had it done professionaly and voila. I can literally shave with it and it seems to be a robust edge to boot. The key here is I had it professionally done.
Handle ego's:
Lock up is always an issue on any liner lock. I feel that the EKI's are very easy to work on and they don't void the warranty if you do. I will say the BEST lock up of any EKI prod. I have owend believe it or not have been on the Ravens I own. These two a spear point p.s. and a tanto p.s. have stood up to some very good and heavy use with no complaints. The lock up on both is left of center and has not moved one iota through repested openings and closings at all. For some reason they are very easy to get sharp and keep sharp. Not like my CQC sharp but still hair poppin.
Hype:
Now as for all the hype surrounding the EKI line well that is just what it is hype pure and simple. I have any number of commercially made folders that I think are much more inlclined to heavy duty use and much more user friendly. User friendly in this case means out in the woods and maybe touching up the edge of the knife on a hand held hone I carry. Two that come to mind are the CS Pro Lite lg and my S2K. Both are bullet proof and are big heavy in the hand feeling folders and take and hold edge. Believe it or not the Pro Lite holds it edge pretty decently for 440A. At least this has been my observation when stump shooting and digging arrows out of stumps etc. I have beat on them with small branches/clubs to make deep v cuts to unsecure an arrow with no ill effects on either knife. Torqued them pretty good to with no liner lock failure either. Truthfully haven't tried this with my EKI's but I think that comes from confidence in the build. These two particualr knive as stated are pretty robust in blade thickness, liner thickness and lock up and just a general sense of heavy dutyness to them.
As for the self defense thing well I am not a martialist with a knife by any stretch but the tests I have conducted for my own satisfaction lead me to conclude that using a knife for s.d. is ultimately a mind set thing. Do you have the balls to cut, stab, or hack someone? Tall order. I have found that my EKI's are not the best for this purpose. Now this is for me. They are liner locks, they have a small blade with no reach, and it depends if you can get sharp enough to cut through material be it wool, canvas, or leather. If I had to pick one of the folding knives I have for s.d. it would be my CS XLG Voyager clip point p.e. It has a bit of reach, gets scary sharp, locksup like a bank vault and no matter what kind of death grip you put on it it aint' gonna accidently close. But all this being said is the reason I have a ccw and have had it for almost 30 yrs. I don't carry a blade for s.d., I carry it for general every day cutting, which the EKI's seem to excell at if sharpened properly.
Now if all you formites want the best made production liner locking folder made today get a S2K. Had to put this in there.
Conclusion:
There is alot of hype surrounding the EKI line. Alot of it deserved just on what I have read about Mr. Emerson. Some of it not deserved. The thing is from what I have read is that he does stand behind his product 100% no matter what. That is probably the biggest plus I have seen of any manufacture'er. Bottom line is that the knives are adequate for what the intended purpose is for and that is for general cutting chores provided they are sharpened correctly. I don't personally think they would stand up to alot of pounding on like my S2K or the Pro Lite. Again haven't tried it but they just don't instill the confidence to do so. Your experience may be different. They don't make that great of s.d. tools imho because of the lack of reach thing but they do have great customer service and the people that own them take great pride in doing so. Alot to be said about that. Keep'em sharp and Happy New Year.