Should I open this?

I bought a SuperYo Renegade off eBay thinking it just came with the box, but it’s still sealed tight. Should I open it up and play with it, or display it on my yoyo shelf?

Play it then display it. I doubt keeping it unopened will add much to your retirement fund.

Yeah, unless you’re a dedicated collector, play it.

so did tom kuhn and duncan sue the pants off this company?

That is a first run Renegade. Notice, it has a hexagonal nut, not a star shaped nut.  All Renegades produced after this run were of a different design (the hex nut is more likely to strip the plastic, while the improved star nuts can’t strip).

I would keep it MIP.

Open it. I don’t think a MIP 'gade is going to increase in value much, and it’s a fun throw although the white ones with the star nut played better. I still have both, the black one is mint because the white got all of the play.