Brilliant! They synthesized something complicated down to dirt simple.
Homebuilders of every type know how many issues can arise from seemingly straightforward fuel system design. Especially with a low wing aircraft.
Fuel control valves have been the source of many maintenence issues and engine failures (valve or pilot induced). The ability to eliminate this device, and all the attendant problems, is a significant achievement.
The one downside here is there does not seem to be the ability to isolate one tank. Perhaps that will be handled separately from the sump? This would is important in case of a leak on one side. Secondly, I frequently run one tank almost dry in my low wing homebuilt. I don't have large storage tanks and this allows me to keep the majority of the fuel in one tank towards the end of the flight. This avoids the heebeegeebees of watching both tank gauges hovering near empty near the end of a longer flight.