With Time Limit, actually, I want it to actually be somewhat fair.

So no golden form?

Wouldn't golden form run out fast?

If it's just golden form, there's a chance for the fusion.

Golden + Jiren's full power then the fusion runs out instantly

How long would the fusion last with Golden Form?

Since the potara lasts for about an hour normally, and Vegito had less than that when he used SSJ Blue and that Final Kamehameha.

And since Golden Frieza was relatively around Blue, and base Jiren is way above Blue, and it's stronger forms, I'd say Gold Frieziren has a good 5-1 Minutes, as a generous guesstimate

Doesn't matter how long the golden form lasts for. It would make him so much stronger and faster that he could one shot Goku in one attack. Assuming he needs it. And DB characters fight at very high speeds, so time usually isn't even a factor.

Jiren with lipstick.. hot

Golden Full Power blitzes lol

Firen > PUI Goku (Enraged) > SFP Jiren >= PUI Goku > Golden Frieza