If I had to choose one, I'd choose my 1/2" Craftsman -v- RP ratchet that my dad bought in the mid-1970's and gave to me when he moved across the country in 1989 (he was a federal agent, so we moved around a lot. I stayed behind for college).
The ratchet is the old pear-shaped RP that has the oil port on the top (which has never been used). It was my first tool, it feels completely solid in my hand, has tasted my blood and has felt my pain. It is my Excalibur. The old RP has never let me down and it's the only tool I own that has a soul because it's been with me since the beginning and it's the only hand tool that was ever gifted to me.
Do I own better wrenches? Probably. More useful ones? Absolutely. But every time I pick up my 1/2" Craftsman -v- RP, it feels right. It's hard to explain, but everything I ever learned about engines, I learned with that wrench.
My dad was going through my toolbox a few months ago and came across "his" old wrench and asked, "Do you still use this? You have a lot of nice new tools in here." I told him, "Forget it. You're not getting it back." Then I turned on the radio, put his car on jack stands and changed out his diff fluid. While I was under the car, I told him, "You're too old to be wrenching anyway."
He kicked me in the foot and slid me a beer. It was a good day.