As Timmy said, keep the fingers off the lock bar. This is very easy for a lefty like me with only a thumb on that side.
It will break in nicely over a few days/weeks depending on your flipping addiction level. The 90 degree edge of hole on the blade will get slightly rounded and the detent gets wonderful. I have been carrying a large 21 and a 781 Anthem for months. Strangely, I had my 0450 today! Awesome knife no matter what your collection contains!