Before setting up the Soverign I used the Gravity One on my old table. It was no contest. MUCH better truth of timbre, greater dynamics, impressive detail, extension, just more of everything you want and none of what you don't.
Hyperbole to the extreme.
The Gravity is just a lightweight tuning device that sits on the record.
It does nothing to flatten records, or couple them to the platter surface.
They would have you believe that if you put a piece of flooby on the record label it will improve the stylus performance 2 inches away on the first track. A 1/2 cup coffee or a lump of your childs playdough sitting on the label could be just as effective.
I have heard the Gravity on a variety of turntables - it is garbage, a con.
For comparison i have in house weights/refelx clamps from Final audio, Micro Seiki, Sota, Goldmund, Audiocraft and many others. I laso have a variety of mats in the house from Final audio, Micro Seiki, SAEC, Godlmnd, Sota, Seisin, Sumiko and many others.
When I heard the Gravity we tried it on a variety of mats and turntables.
Yes it slightly altered the sound, improvement - no,.
The worst record weight I have ever heard was the much vaunted "Stillpoints" - again tried on a variety of turntables and mats - worse than useless, although it added a little sharpness it muddied up the upper midrange lower treble by some degree compared to other designs.
There is no "best" weight or platter mat becuase the outcome of any of these aftermarket products is going to depend on the platter construction of each particular turntable and the tracking ability and sound quality of your particular arm/cartridge/phono combination.
This is why I keep library of platter mats and weights/clamps on hand. It can be illuminating to revisit them from time to time when I am setting up turntables.
To believe that a specific weight/clamp solution will be effective on every turntable no matter what the construction is illogical and foolish.