It will work fine.
I find a huge amount of coins and I supertune most of the time.
Last fall I used my Vaq was in a very old historical estate that had a ton of iron from large to small everywhere.
Supertuned the real big stuff overloaded, the smaller stuff I knew was iron because it painted to big to be coin sized and was a little too loud and the real small stuff sounded different than other targets so I could tell.
I dug a bunch of iron here anyway because it could have been cool and our club was trying to gather relics from the property to present as a display, but I know enough about my Vaq to know iron of all kinds more often than not.
I have the high tone model so that might have helped in some way, but I really have no idea how the low tone models work exactly on the Vaq or Cibola because I have never swung one.
Even in all this iron and other trash, modern and old, I was still able to find and easily free this thing from mother earth at about 4-5" in depth.