[Arran]

Just for grins I like to test some of the capacitors I replace.  I also test the new caps I put in since most come from China and I like to verify they are-what-they-are.  Most of the time they are fine, but I have found a couple of off-value "yellow devils" as I like to call them. 

Because I want to check these under voltage I use a vintage Jackson 650A that has served me well over the years.  I also have a Heathkit but I like using the Jackson a little better.

 I do that as well, truth be told I don't know where some of the yellow ones were made, Taiwan or China, but most have nothing but a value written in Pf and a voltage, no name, so none the less I still test them. Once I got a capacitor tester, or more acurately a resistance-capacitance bridge, I started testing everything because I used to buy a lot of NOS parts from a surplus house in Montreal, and also from estate/garage sales. I found some duds among the NOS ones I had, culled them from my stash, and just never broke the habit of testing any new ones I picked up. I have two cap checkers, one is an Eico, the other a PICO, the PICO seems to be more accurate for testing values.
Regards
Arran