Umnumzaans and 25's lock up

[Blades'n'45]

So with all the talk with frame locks that usually go on in the forums I thought I'd like to get your guys thoughts on the 25 and umnumzaans particular lock up design. As far as I know these two knives are the only frame locks that share the ceramic ball lock up. I think it really is an ingenious design feature that solves the problem of lock wear. And from what I've seen and heard it seems like there are less warranty problems with the umnums hence why
Mr. Reeve decided to implement the same lock up design on the 25.
What have your guys experience been with these two knives? Has your umnums or 25's lock ever failed/ disengaged? Do you prefer the lock up this way or do you like the 21's better? And why haven't other knife makers tried implementing this feature on their frame locks?

 

[1AbominAble1]

I carried an umnum over two years as my edc, there were very few days in that time that I carried a different knife. In all that time and use it never failed or slipped, in fact, after two years I took it apart and cleaned it up, when I put it back together the lock up was better than it had been
The only thing I can think of to answer why was that the pivot must be ever so slightly out of round or the scales are just a hair off from where they'd been- no complaints, I love that knife!

It took me a long time to love the ceramic ball interface and with the flex of the lock bar on the umnum I was concerned that it'd fail. My concerns were proven to be unfounded and I grew to really like the smoothness of the design.
Fast forward to the knife that knocked it out of my pocket, the 25, the ball is bigger giving a nicer detent and the design eliminates the lock bar flex. It has the same blade and handle stock as well as a grind that makes it cut like a laserbeam through fog. I think that the 25 is a better knife, a refined umnumzaan if you will, but I still love my umnum's for the differences. I like how your hand is closer to the beginning of the edge on the umnum and the quiet action of it opening and closing, I also like the feel of the handle as the lines are very similar to the Large Regular Sebenza.

With all of that said I can't tell you which style I prefer. I carried Sebenza's for a long time and never had a problem with the lock wearing so I'm not really sure what the ceramic ball is bringing to the party. The only thing I can say is that although it has proven to be unnecessary I do prefer that there's more material holding the tang in place on the Sebenza.

I solved this problem by buying three umnumzaan's and a 25 for further testing but somehow my large and small Insingo's keep finding their way into my pocket, I guess I'm hopeless

 

[LonnyRS]

My 25 has never failed in any way. I can see where the ceramic ball makes contact with the tang, and it has made awear spot there. I have tested to see if it's made a groove with the tip of a pick, and it's completely smooth. So really what is happening is the ball is polishing the tang in that small area...