How much of a boost does Babidi's magic give?

[Cell-Max]

I was reading about Dabura's hypothetical strength with the third eye and it got me thinking... just how much of a boost does Babidi's spell give? Is it a set amount or does it depend on the relative evil or strength of his victim?

 

[DBZAOTA482]

Depends on the victim. Highly training fighters who've already trained their bodies close to their limits like Vegeta or Dabura, the Majin charm would only provide a marginal increase (2x at best).

But for regular Earthlings who likely have no concept of ki like Spopovich or Yamu, there's plenty of room to work with and the Majin charm pushes FAR beyond their natural limitations.