My first was a Digitech GSP Legend 21 I bought used in the mid '90s but it had a lot of problems so I brought it back and got a Valve FX instead. Since the Legend was basically unusable I consider the VFX to be my first.
I still have it in a closet in my gear room. I broke it out early last year and put it up for sale when I ordered my FM3T. Then I committed
THE big mistake and tried it out with a couple of amp in a box type pedals in front of it. Naturally it sounded better than I remember it ever sounding and I promptly deleted my listing.
Where is it today? You probably guessed, back in that closet and hasn't been used since this experiment.
When you decide to let something go NEVER try it again, just sell it and don't look back. My closet is stuffed with unused crap due to not following that rule.