Superman says "lets feel each other out first":
http://i.imgur.com/ECWFHp9.jpg
Cyborg is roughly around the same level, even if you think bizzaro is stronger, goku can't survive a hit like that. While we constantly talk about the earth be blown up by them, why is the earth killing them itself ignored? LAVA is dangerous to them, so how is ki going to help them in a fight with supes? Do you know how impressive the feat above is to supes and how worse it for goku? The lower mantle of the earth can reach temps from 1,800-6,300 degrees (sorry krillin.), while the inner core reaches up to 7,200-8,500 degrees. You simple if you ignore dbs writer intentions for selecting the things they face (not on supes level) only to be ignored (vegeta against lava, dying by a planet and goku getting hurt by bullets and a laser beam.). Lets get physical? Superman is lifting stars blackhole) while goku lifting weights that don't come close in comparison to a star on King Kai's planet (stop looking what he may become and use actual feats being shown in the anime or manga-anime is better-and stop robbing supes feats.). The earth is big enough, but there's objects on earth or parts of the eArth that goku can't even lift, like the earth's plates. The largest plate on eArth is around 42 million square miles (king Kai's planet is small) while each individually is around 60 miles thick. Sooo cyborg stomps, and while you're thinking, which is greater? Ki or physical strength? (Supes body isn't rock that can be broken, causing a chain reaction like earth.) And if you say ki because planet destruction then they could just ignore getting physical!
