I see .. so that cleared it up.
As far as Goku (Power Level 340) and Dante stand, how did you come to the conclusion, I would like to know that.
To be honest, I am horrible at "doing the math" involved in these types of scenarios, but for the sake of conversation, I'll try. ^^;
There are others things to take into consideration, besides feats of strength, power levels, etc. Speed plays a factor, as does intelligence, tactics/fighting styles, and defense. It's been awhile since I watched any DBZ, so I have a very vague recollection of when Goku achieved what ability...but at the stage you're dictating, he didn't have instant transmission yet, right?
Assuming he didn't, he still was quite fast-but then again, so is Dante. We see examples of Dante's speed in terms of evading enemy attacks, blocking enemy attacks, and the lightning output he performs when pulling the triggers on his guns.
In terms of feats of strength...well, there are many examples there, as well. Beating Mundus was rather impressive, given the fact that the Demon King was unbeatable to most everyone else-excluding Sparda. Despite not being able to kill him, Dante did manage to cause enough damage to prevent Mundus from returning (though granted, some say that due to being in the human world, Mundus didn't have full access to his powers at the time of their battle; I'm not too sure about that, myself).
We also see Dante block a giant fist of the Savior statue, like it was nothing-though we see the impact crater beneath him, from where he dug his heels in, which suggests the hit was both fast and powerful.
I would never dare underestimate Goku's strength, speed, or character-but between the two of them, both of them enjoying a worthy opponent and all, I think Goku is far more laid back (which is saying something, considering how mellow Dante can get at times) and I think as far as intelligence goes, Dante has the lion's share.
Not saying Goku is stupid by any stretch, but certainly more light-hearted.
I could be way off-base with my conclusion-either way, it would be one hell of a match.