Magicman, you wont be dissappointed with the N-Tune dial, And shipping will be quick..

HSN=High Speed Needle
LSN=Low Speed Needle

No I have not changed ANY screws to Flat blade or Phllips, I believe the hex's work VERY well. In fact, so much so I replaced all of the Phillips on my truck. Sometimes you have to use heat via pen torch or something that makes good heat, to melt the threadlock to loosen those stuborn screws.

Hope that helps