My opinion;
What program is on the ESCs you have? If some stock configuration, likely mod 12th scale could benefit from a better profile. This would require some testing as I have not seen a mod 12th scale program suggestion.

As for the 19T, I used an 8T pavement profile on my 19T carpet then switched to 19T carpet profile. VERY little difference. More patience may have yielded more info but.. that is not my forte. These ESC are so good in my opinion, hard to imagine a huge jump in performance from where they are.

Todd