How accurate are budget moisture meters under $50?

Specialist community consensus is that sub-$50 meters are reliable for RELATIVE readings (comparing one piece of wood to another, or tracking change over time) but absolute accuracy drifts, especially above 15% moisture content. Independent bench tests of popular budget units have flagged poor accuracy at the high and low ends of the scale. For firewood, DIY, and most hobby woodworking that's fine; for flooring installation or insurance-grade inspections, it isn't.