uhhhhhhhhhh No!! this makes utterly no sense, considering the fact that kishimoto has never shown us a 6 or 7 gated guy moving from point A to point B. so you have no right to make such nonsensical assertions.
you people unfathomably overrate A's lightning armour. ya'll really think that his lightning armor Augments his speed which is clearly false!
Raikage's speed is naturally fast! his lightning armour only augments his reflexes and chakra levels, "stated by shee and karin." and he combines that bijuu level chakra with his the "body flicker jutsu" which grants him the ability to traverse short distances "almost" instantly. hence the reason why he was able to dodge amaterasu.
the body flicker technique is something gai does not use. he uses his natural body acceleration speed which is clearly super sonic or maybe even hypersonic. "Hence" the fact that his striking speed is fast enough to ignite the atmosphere. it's only common sense that his acceleration speed is the same thing.
im going to be making a thread about the raikage's speed soon. to clear up a few things for you people