shadow and sonic vs goku and vegeta

If you base the fight on how Sonic and Shadow were in Sonic Adventure 2 / Sonic Adventure 2 Battle, in their form they both gain from the chaos emeralds, they would simply be invulnerable, but unable to keep up with Goku and Vegeta; they simply last until they had no more rings left.

Now if we base this on Sonic X, they may be able to go toe to toe with both Goku and Vegeta, but barely. But the form Sonic gets in Sonic X, when he turns black, he may be able to last longer with that.

Depends on what time you are talking about are you saying when Sonic was a child and Goku was a child or when Shadow was first created and when Vegeta was just a child. Or that when they're adults {I don't know what age Sonic and Shadow are so I'll just say adults} Or are you saying when Super Sonic, Super Shadow, vs Super Vegeta and Super Goku. Or Hyper Sonic, and Hyper Shadow vs Super Sayin {I don't know how to spell it} god Goku and Super sayin Vegeta. Because they grow more powerful during the years. So I can't answer this question directly the way you want it.