[jerryhawthorne]

ODPILOT, you will get more answers from that question and they will all vary. I have a Precision 10-12 which is a low end tube tester but will test any tube I can come up with. Testing is a word that is rather ambiguous as some test more factors than others. Mine is an emission tester but it does handle dead and shorted tubes which I'm most interested in and provide an idea of emission of the tube. Others will provide more precise information on tube function. I will say radio tubes that test weak on any tester seem to work just fine. All bets are off on oscillator tubes as no reasonably priced tester will tell you if they are going to work at higher frequencies. The best tester is the radio with a known good tube that works in another radio.
If you wish to match output tubes in a high end piece of audio equipment, the more expensive ones are nice. I don't need that just a rough test.

Good luck on your search and match your needs to a product. Particular emphasis on will it handle your tubes. Often "new" ones won't handle tubes from the 30s due to sockets for them not being there.
Happy with what mine does as a rough check and to make certain I don't plug a tube in that is going to hurt something else in the radio.

Jerry