Heal/DPS Build question

[fishyyy]

My build will have a first bar with resto staff and healing support abilities and a second bar with a desto staff.
I went through several posts to figure out that abilities like Surge and Molten Weapons increase your weapon damage and thus increasing your healing and your damage with staff abilities.

So how I am deciding on which class I choose will be if Surge or Molten Weapons can give me the best Weapon boost. Does anyone have numbers, videos that I could use for a comparison?

I just found one video from a V6 Player that has Surge improving +58 weapon damage. But how does Molten Weapons scale up?

Thanks&looking forward for replys