An Achilles Tang is way too fragile - if it dies travelling - there will be no exchange for the new one. Take my word. It happened to me.
Sohal is fisty but when you release it to your tank together with,
let's see, Purple Tang, at the same time they will not fight...
Three years ago these two rascals joined my tank (200) and since than ignore each other totally.
They will be after other fish (Sohal cannot stand my Fox, chase goes on); Purple Tang forced Yellow Tang to jump out (I tried to save it from being trashed by... someone). Didn't work, anyway.
Sohal grows slow but it gets big (in the big water to 16"!)
If this will be the only large-to-be fish in your tank - 125 is not soo bad. But after, let say, 3 years there will be a problem.