GRT was using Floscan 201B and now have changed to EI FT-60 (Red cube). I had the Floscan and it was pretty accurate (in the tunnel) within 1 Gallon for every 30 gallon of burn but it was weeping fuel out of the plastic part that the wires go in it. So, I changed it to the Red cube and was very disappointed that Floscan was not willing to replace it even though it was obvious that it was faulty. I have the red cube now and have installed it in the same location. It seems every more accurate .2 Gallon off for every 25 gallon, and it seems to be built better.