I moved on from these devices and now just use common sense
I wouldn't print without one, and have 3 as backups. For developing since I use a water jacket at 68 deg, it's kind of superfluous. You can also use the RH Design one for a bit more money, but newer with a warranty. L
Try doing color separation negatives or anything critical by inspection! In that case, "good enough for government work" ain't anywhere near good enough.
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