First of all, every other bf109 at various BR has an advantage over most of their rival aircraft in one way or the other for their respective BR !
But in the case of the G-14 every other plane it faces have equal or better climb, speed and agility
you would climb high up as much u can but still face spitfires and p51 in front of u !
Finally, the G14 does not have any major upgrade over its previous G6 to be in a BR 0.6 higher than the g6
It would meaningful only if it’s BR is lowered to 5.0!!!