@niBBit: Power scaling is fun and all but it doesn't really help here. A lot of people agree that Super Saiyan Vegetto and SSJ 4 Goku through power scaling are roughly the same. However Fusion between Goku and Vegeta during Battle of the Gods didn't happen despite being allowed a lot of time which indicates to me that it would have been useless. This to me means SSJ God Goku >SSJ Vegetto/SSJ4 Goku. Meanwhile Birusu is still able to take down SSJG Goku comfortably with power to spare so that would put Birusu>SSJG Goku>SSJ4 Goku. Through scaling he is around Yi Xing Long's level and through feats and statements of his power(FTL speeds,casual solar system buster possibly even Galaxy level) he takes it. Simple as that.
So many wrong statements e.e
1. SSJ Vegetto is not equal to shadow dragons saga SSJ 4 Goku, but ssj2 vegetto is ( by powerscaling )
2. There are no potara earrings anymore and Vegitto >> Gogeta
3. Birisu did not beat goku comfortably, he tried to bust the planet after the fight yet he only busted a rock.
1. No potara earrings doesn't mean squat. They could still fuse to become Gogeta and go to ssj2 or ssj3 and yet didn't. Also Vegetto is only at best slightly more powerful than Gogeta. There really isn't much evidence to suggest he's a lot stronger.
2. Birusu only used 70% of his power to beat SSJG Goku. While 30% doesn't sound like much it really is. Goku when he turned Super Saiyan was only 20% stronger than Freeza. This difference however was huge as Goku held back and still thrashed him. Then later on when Freeza fought a super saiyan who didn't hold back he was killed almost instantaneously. There's a reason why Birusu called Super Saiyan God overrated and it is that he most likely would have beaten him nearly immediately if he wasn't holding back. Goku getting him to use up his power was either dumb luck or the result of Birusu waking up early. Had he gone all out Goku would not have had a chance.
3. Even using power scaling for GT is difficult since it would take Golden Oozaru Baby multiple blasts to destroy the earth and the most power Yi Xing Long was stated to have even attempted in battle was maybe planet busting. Compared to a FTL casual solar system buster these guys are cupcakes. Power scaling works well when you at least have the feeling that the later characters can match what happend before but with GT I never got that feeling because every time they tried they failed miserably.