Anybody use one of the cheap fuel gauge converters?

I finished testing and plotting the gauge response and found it to be far from linear (although I only know the sender resistance end points from the test I did when I had it out last year). Those 1000 piece resistor kits and cheapo variable voltage DC power supplies come in handy. I cancelled the Amazon FM101 converter as its only 3 point and bit the bullet and ordered the 4 point MeterMatch unit through Summit as shipping was a bit cheaper than buying direct).