Gogeta wins this. I once already explanied my opinion as to why i think Gogeta and Vegito are even in power but shall do so again: Most people believe that the Potaro Earings are stronger than the fusion dance beacause of these reasons: The Old kai said so or that the Fusion Dance is weaker because it requiers both fighters to have equal PL.
First lets start with Old Kai, Old Kai never once stated that the Potaro Earings are stronger than the Fusion Dance, the only thing he stated was that the Earings are more effective, we get to that in a bit.
Now the Fusion Dance, in order to PEFORM the Fusion both fighters must have the same PL in order to merge right? so by that logic people always assumed that thats why the Potaro are more powerfull because there is no need to match eachothers PL in order to fuse, but there is no indication whatsoever that the Fused fighters can't access or reach his full power. Lets say Goku and Vegeta are going to fuse like they did so in the Janemba movie in base form i must add both of them weren't even at there MAX like Goku's SSJ3 or Vegeta's SSJ2, Goku at lets say SSJ2 needs to lower is PL to match Vegeta's SSJ2 form since Goku is stronger right? well....where does the power go to? does it magicaly dissapear into thin air when Gogeta is born? does Gogeta who is born from the 2 greatest warriors in all of DBZ suddenly gets struck by retardation and forgets he has more power but somehow forgot it or doesn't know how to access it? no the power doesn't get erased from there being it isn't locked away for some unknown reasons that power was yours to begin with so it can be access later on when needed.
Now the the Old Kai only said that the Earings are more EFFECTIVE, effective doesn't mean that its more powerfull and he later on explained it to Goku who said he wanted to do a Fusion Dance with Gohan in order to beat Buutenks:
Goku: Wait! i know i will just do a Fusion with Gohan and then we are bound to win right!
Old Kai: Ah Fusion...you mean off the type those kids have been using? you think Majin Buu will sit on his laurels and wait for you to get in just the right stance?
And thats why the Fusion Dance is so stupid...in a real battle no opponent will just sit there al let you do your little magic no he will rush you and beat the crap out of you and he will succeeed since the Fusion Dance takes time to peform but, not so with the Earings with the Earings you just slap them on and BAM! Ultimate Warrior ready no fuss no huss no nothing BOEM! ready to go to battle... EFFECTIVE.
Look at Gotenks for a bit.... the power he recieved from the fusion is simple Godlike. Goten at even SSJ could't even hope to match someone like lets say SPC or an FSSJ yet when they fused they went from a mere SSJ who can't take somebody in an FSSJ lvl (example) to going head to head with Super Buu such an power boost is dimple grotesque. Even at base Gotenks put up a decent enough fight against Fat Buu and at SSJ lvl he could maybe beat him and Fat Buu is an SSJ3 opponent. Now this was Goten and Trunks imagine Goku and Vegeta doing this who are infinitly more powerfull than Goten/Trunks...don't you think after looking what kind of godly powerboost it gets that they can't supass Gohan or Gotenks?
Sadly this isn't my fullest info as to why i personaly think that Gogeta and Vegito are even in power but i'm tired didn't sleep at all so i check in tonight and will update on this so as for this match Gogeta stomps the team if Vegito at base could handle Mystic Buu than Gogeta at freaking SSJ would murder them.