As I said earlier, the sub $10 meters with 3 point calibration and 0.01pH resolution and claimed +/- 0.01pH accuracy are much, much better than strips. They are also an order of magnitude better than the ones with screwdriver based calibration at pretty much the same price point.
I have this one: https://www.aliexpress.com/item/Pro...-Measurement-Range-Automatic/32838415541.html
Used it twice and so far no issues. Calibration has not drifted in the 3 days between uses.
I have this one: https://www.aliexpress.com/item/Pro...-Measurement-Range-Automatic/32838415541.html
Used it twice and so far no issues. Calibration has not drifted in the 3 days between uses.