I absolutely love my 561 NOW..... When I first got it, it was stiff as all get out. It took a ton of force to get the blade out and then to release the lock to close it. I tossed it up to tight tolerances from a quality product. As such I flipped that sucker probably 1000 times. I like the flipper but Im a thumb stud guy so I insisted that it be able to open with that option. I developed a nice callus due to all of this flipping.
My persistence has completely paid off. Now, after 1000 or so flips this thing opens like a slingshot. It now opens like one of my assisted knives. And it now closes just as easily. I prefer this knife over all of my $400 plus production knives and I have a few.