* Different Universes: Sonic the Hedgehog and Dragon Ball exist in separate fictional universes with entirely different power scaling systems. There is no official crossover or definitive way to compare their power levels.
* Solar Sonic's Power is Vague: While Sonic has achieved various power-ups, "Solar Sonic" isn't a specific, officially defined form with concrete power levels. It's more of a fan-made concept.
* Goku's Power Varies: Goku's strength has constantly evolved throughout the Dragon Ball series, with each new transformation exceeding the last. SS3 is a powerful form, but later forms like Super Saiyan God and Ultra Instinct are vastly superior.
To fairly compare these characters, we'd need:
* Official Crossover Material: A story where Sonic and Goku interact would establish a direct power comparison.
* Definitive Power Levels: Specific, quantifiable power levels for both Solar Sonic and Goku's different forms.
For now, the answer depends on how you interpret their powers and what assumptions you make. Both characters are incredibly powerful within their respective universes, but their strength is difficult to compare across those universes.