I've been using one for over a year now. I like it. Keep the tip clean to prevent false readings. Also, has to be pushed straight in for accurate readings. I think I paid $60 for it.
BTW, I still weight the tanks when I want to be precise...
2000 Cherokee 29BH with 6V batteries, LED lights & 400 watts of solar power, flipped axles and raised. 2007 Tundra 5.7L DC-LB with lots of mods. C-co, 8/158th AVN Maint.