Many moons ago, I bought a press.  Boy, was that the way to go over a Lee hand loader.  Over the years, there have been many things that made life easier that now I couldn't be without.  Many have already been mentioned.  The last two items are a Wilson trimmer, which seems to cut so much faster than the RCBS that I had (other than the Dillon RT1200).  And the RCBS hand primer that doesn't require a seperate case holder.

A tie between the Chargemaster for  hunting loads vs  my 650 with all the bells and whistles for volume loading