E-Revo gearing with Revo Transmission

[Happywing]

I'm working on a conversion with a custom builder. He says that I should use Jato spur gears 54,56,58T and about a 26T pinion. With my cheapo gearing calculator, I've arrived at the same final gear ratio using a stock Revo Spur (40T) and a 19T pinion. They arrive at nearly the same final number, so what would be better and why 26/56 or 19/40? There must be a difference, but I lack the know-how to figure it out.