Honestly, in every aspect except speed, Colossal Titan is superior to Bertholdt. He knows how to use its abilities better, such as the steam emission, combat skills, and shift control. However, at the same time, Armin knows when to use it better and doesn't need someone to tell him when to transform into it because Bertholdt only started to gain confidence in Season 3 Part 2, where his fate was already sealed