A strange looking pentacopter and I must say I have been thinking about fitting a rear motor like that on one of my quads myself:

https://www.foxtechfpv.com/foxtech-screa...r-rtf.html

It would be interesting to try one of those, but I'm not sure how to control the throttle on the rear motor

That is interesting. Can you imagine what yaw turns would be like? I see they have settings for Naze and F3 linked on the product page.

Awaiting a product review....

From the manual, it looks like you have to connect the booster motor to a spare PWM output on the receiver and set up a separate channel on your receiver to turn control the speed, so I guess we are talking more or less about some kind of fixed speed on the booster motor while you are flying. Maybe a PS4 style controller with analog buttons in the front would be better suited for something like this

I think their battery life estimates are a bit optimistic for aggressive flying.........