All Pearl River GP212 models, regardless of the brand on the fallboard, are the same. The GH212 is a substantial upgrade from the GP212. The GP212 hosts an "all spruce" soundboard whereas the GH212 has a solid European spruce soundboard. The GH212 has a completely Chinese producted action (all components) and the GH212 has some European components, including Renner hammer heads. Most importantly, the GP 212 was NOT designed by Lothar Thoma, whereas the GH212 is a Thomma design.
I hope the above was helpful.
I'm sure it was helpful in the full-blown Northeast US sense of the phrase, but I'm not sure it's accurate.
Not to be a tedious bore
, but according to Pearl River's own marketing materials in China, the two largest models of the R1 series (the GP212R1 and the GP275R1) both employ a Renner action made in Germany as standard equipment (not that this is necessarily a huge advantage at this point in time since theoretically at least, the Chinese may have figured out how to duplicate Renner design and quality at a fraction of its cost). The same "Renner action made in Germany"
claim is made in Pearl's Russian marketing. So, if it is indeed a fact that there is no difference in any versions of the GP212, this is an unfortunate marketing misstatement by Pearl.
The OP is in Kuala Lumpur, Malaysia, which of course is not Russia or China. However, I think there's a strong likelihood that the GP212R1 sold there is identical to the one sold in China and Russia, and is not a piano sold in the US.
Since no claim is made for the soundboard other than all-spruce, I agree with you that the board employed is likely a solid core sandwich and not a solid board (not that that's a bad thing except for piano makers trying to dance their way around it).
As for Herr Thomma, I didn't warn the OP that Herr Thomma may not have been supervising every aspect of the production of the piano he is contemplating buying. After all, there's only so much one man can do, even Herr Thomma. Since Pearl built pianos before the Thomma 'intervention' and continues to build pianos which he does not personally carry down from Mount Sinai on his back, I think it may have reached the overkill stage of tossing props to Herr Thomma (even if it's true as I've heard from Norbert that the locals in Guangzhou didn't know how to manipulate their chopsticks properly until his arrival).
Now, what I really want to know is whether the Sauter Omega shares the dubious distinction with the Pearl River GP series of not having been designed by Herr Thomma. That would be a pity.