Benzaah ... 35mins .... ouch !!!!
Any speed for 35 mins would put the motor at risk. Just would get too hot and kill the motor.
These are good systems but are designed like most systems .. for use over a shorter period of time.
I look at this way .. would you run a 17.5 or 10.5 around for 35 mins?
There are a few different sensorless motors available. Hobbywing do a full size 17.5 sensorless motor