CMS36-5700 vs 6900

[wevie]

I have a T4 running a MM5700 combo. Normally I run the truck on 2s. Just for kicks today I wired two 2s packs in series and added a receiver pack. Since the 5700 is not rated for 4s I only ran a couple of bursts out in the yard. Needless to say, the truck really woke up, but it is definitely a little too much.

I'm wondering what kind of power/speed increase I would see going from the 5700 on 2s to the 6900 on 2s?

My other option would be to buy new batteries and run the 5700 on 3s.