RE: Should I be crimping?
Well I guess we all have different opinions. Crimping may or may not improve your accuracy. I've had it work with some rifles but not others. The Lee factory die only cost about $8 so its not like its going to break you to see if you can mill that extra 1/10" out of your load.
The theory is that a crimp give the bullet a consistant starting pressure. Does it work? You will have to be the judge.
I crimp some loads for some rifles but mostly I don't bother.