How good is the Obsidian plinth of Technics SP10 ?


Recently I heard an SP10 MK2 playing music at a friend's place. It was mounted on the stock Obsidian plinth. It actually sounded very good. I wonder how good is the Obsidian plinth compared to:

1. Typical after market birch ply plinths ?

2. Custom designed plinth like the Panzerholz plinths made by Albert Porter ?

Any ideas ?
pani
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some golden ears claim that the obsidian plinth is too monotonous on the bass range compared to plinths in birch plywood or decidedly heavier plinths.
I do not believe it very much.
Has anyone tried using the Sp10 Mk2 naked (without plinth and directly on some footers) ?  What can be expected from such an arrangement ?
Thanks @chakster .

@raulrigas, what are your impressions of driving the SP10 in the naked mode ? Do you advise getting a good plinth ?