[Botwoon]

I've used neither, but I can draw on enough of my experience to tell you that Mek drivetrains don't hold a candle to swerve in terms of speed, traction, efficiency, agility, etc.

This is of course assuming that you have the necessary resources to properly build and implement a swerve drive over the course of the season, and that you have enough of those resources to ensure that building a swerve drivetrain won't hurt the rest of your development. Keep in mind how many teams have won championships on swerve drives; it's a small number.