If I do use it it’s too record video with the drone staying in a straight line. 
then cancel it before it’s back.
When starting out, I used to use it frequently. But now hard use it at all. If I need to get back quickly for whatever reason, and VLOS is struggle (due to distance, sun or low light), I find using the map feature much easier and safer. I mention ‘safer’ as sometimes, the RTH fixed altitude plays against you, and can cause more harm than good.
I use RTH maybe once every 6 flights. Just to check it is working.