yep not problem free that's for sure. Major problem is that weather is almost always adverse when you want to use them most especially on long campaign fires. Think bad weather in CA.A pretty consistent problem with drones is stewardship. A police force or roofing company or rescue service will buy a drone and it will sit in a closet until they need it. Rarely are considerations made for maintenance. This week alone I've had 3 Mavic Pro batteries and 3 Inspire 1 batteries brought to me; "Can you fix these?" "Sorry...no...I can't. They sat in a closet for 1.5 years. You get what you get."
This multiplies when you have a gas engine. Drone stewardship is a hands-on responsibility. Drones must be used regularly (I personally recommend twice a month minimal), and batteries must be stored and discharged correctly (0% every 10 flights). NOBODY does this. So I can imagine this gas-powered drone (2-stroke, I imagine) will have old gas sitting in the tank for months on end. Or batteries stored with 100% capacity because the on-board generator keeps them charged.
All that said, this seems like an awesome drone. Let's see if it actually gets built.