First set of polyhedral dice you owned. Do you still use them?
Those would be the ones packaged with the Moldvay Basic rules. This was literally the first time I had ever seen dice other than the ordinary six-sided ones with pips instead of numbers, and I was instantly fascinated. There's something about polyhedral solids that does to my brain what a point of red laser light does to a cat's.
Having never seen better examples of the genus, I didn't realize how cheap and shoddy these ones were. They were plastic, a bit misshapen, rather too light, and a bit hard to read because the numbers were not colored. The dice themselves were dully colored - orange for the d4 and d12, yellow for the d8, and a nasty brownish-mauve for the d6, d10, and d20. The material wasn't terribly durable; after a few months' use the corners started to blunt. I'm sure they didn't roll true; in fact, that may have contributed to the low mortality rate in my first games. The d20 tended toward middle teens, a point at which characters could hit the typical 5-7 AC of most monsters, but a 1 or 2 HD monster wouldn't hit the AC2 of a plate-clad fighter with a shield.
The Mentzer-edition Expert Rules came with a new set of dice - an unexpected surprise. The new ones were larger, of harder material, with a satisfying heft to them. They were vividly colored, and the numbers were painted in white for easy visibility. Once we had those, nobody wanted to roll those wobbly butt-ugly old ones or squint at their distorted, uncolored numbers any more, and they were relegated to backup dice. I think I still have the d12 and the d6 in my dice box, but they haven't seen use in years. The others were all lost somewhere along the way. I don't miss them at all in terms of utility, but I wish I would have kept better track of them for nostalgia's sake.