Hey Colin,
As we discussed at Dojo, the single ESCs are much likely a better choice for you now. Much lighter and less space consuming than the Cytron.
The transmitters you use will have no problem with adding mixing. The BBB lads have a good guide here:
https://shop.bristolbotbuilders.com/mixing/#mixing
Any issues, give me a shout or I can go through it with you next Dojo.
Bookmarks