My first HP was a 41CV that was given to me around 1986~87 by a mechanical engineer at the automation company where we both worked. It had been issued to him in the military, and when he completed service, he had left the 41 in a drawer (heaven forbid!) for what must have been a couple years. When I mentioned I was going to buy an HP, he said I could have his 41 because the batteries leaked and it didn't work anymore.
I sent the 41 to HP (with the batteries still in it) for repair. A couple days later I received a letter from HP stating the repair would cost $90 and that I needed to sign the authorization line and mail them $90 before work could begin. I waited a couple days debating whether I wanted to spend $90 and end up with a still used but repaired calculator (the letter didn't say an HP "repair" actually meant "replace with new".. remember, it was my first dealings with HP).
A day or two later, a box arrived at my house with a brand new 41CV and another letter from HP indicating that since I didn't cause the damage, but rather the leaking batteries did, they simply sent me the new calculator and sent the $90 repair bill to the battery manufacturer (Eveready or Duracell, can't remember which).
Needless to say, I was absolutely sold on HP quality and customer service. I now have 40+ HP's.
Oh yeah, I did give my mechanical engineer friend $50 as a peace offering, since I was often found proudly gloating over my new --free-- HP.
Matt