Most Hickok testers. Anode voltage is unrealistic low. There are many work arounds inside the tester, to deal with that problem, like adpating the test data for this, but in the end you can use those a Hickoko only as very reliable "good-bad" indicator. It means you can not verify test data with a Hickok very precise.
All AVO testers. These give too low Anode current with low impedance tubes. Measured Anode current is up to 35% too low with any tube having Anode impedance at or below 700 Ohms. The error gets less with higher versions.
Testers you can use. Incomplete list:
Russian L3-3, though this tester can only test at maximum 300V, so not test all tubes we build. However L3-3 is ideal for 300B, 2A3, and rectifiers.
uTrace, from Ronald Dekker in the Netherlands. A rising star! This is a DIY tester, but it is simple to build and yet a very professional product.
Roetest , From Helmut Weigel in Germany. Highly sophisticated product. This is the most sophisticated DIY tester I know.
Sofia Tester. Rare and expensive vintage product. Call it impossible to find.