Grounding boxes which ones have YOU tried? And results?


Just curious have never tried the many grounding devices that can be found on the web from companies such as: Synergistic Research, TELOS, Entreg, Nordost - QRT, Audio Magic -Blue Dot Eliminator, Signal Ground Solution or many DIY. Do they do what is claimed? Are they worth the $$ which are from a few hundred to many, many thousands! Which units have you tried/used and what were your results?
rsf507
Chayro-- Thanks.    (Now I just have to determine what 'ground lifting' means!   But i believe it means-- get in there; don't electrocute yourself; and find out what the problem is the hard way.)
@jdane - ground lifting means buying an adaptor plug without a ground pin and sticking it on the end of one of the power cords until you find the one causing the hum.  It is not the optimum cure, but it is worth a try. 
https://www.amazon.com/Cable-Matters-Polarized-Grounding-Adapter/dp/B01M0FXMFK/ref=sr_1_3?crid=27L33...
I have tried the Synergistic block with their HD power cord up grade and was very disappointed.
Pretty sure I have one of those in a box somewhere, along with a bunch of other stuff, just sitting there waiting for when I can find the time to hook it all up and listen.   

In the mean time, there are so many different things going on here I cannot even begin to tell you.