First let me say that my Southard has been great and it really didn't need any improvements. It has a strong detent and flipped well. However, it's not as free moving as some other knives I have. I've been hearing how wonderful the Taco and Skiff bearings are so I thought I try a set. So I ordered a set of Taco bearings for the Southard.
I installed them tonight and it was easy enough. While I had the knife apart I noticed the detent ball had a tiny flat spot on the end. So I went ahead and changed that to a ceramic one. I re-assembled the knife and it wasn't really any better than it was with the old bearing. It wasn't bad but it didn't have the Shiro-like action I was envisioning. It just felt pretty much the same as it did with the original bearings. What I didn't like was that the blade felt noticeably more sloppy when I unlocked it and started to close. Yet the blade still was as free moving as I thought is should be. I could see it was back together correctly. So I messed around with it a little more and decided to put the old bearings back in. It's actually better now than it ever was. I assume that's due to the ceramic detent ball.
So for me the Taco bearings were kind of a bust. They're probably great for someone with a knife that has bad bearings but I didn't see any real improvement
On another note, I finally did the detent mod on my Mantra today. It's now better than it ever was. As I posted a couple years ago. The detent ball had a big flat spot and I had flipped it over and re-installed it. When I took the knife apart today I was expecting to have to replace the detent ball with one of the ceramic ones I now have. Surprisingly it was still fine. So I went ahead and did the detent mod and put it back together to test. It was really good as is. So I just left it. I'll change out the detent ball some other time.