Well, I've tried SatoshiGems and don't like it. Why? For one single reason. Unlike Blockchain-Reaction, SatoshiGems is not pure skill based, but has significant luck factor. In case of B-C current configuration on the playfield depends only on moves of players done so far. In case of SG, playfield configuration obviously depends (sometimes in a critical way) on order of randomly selected gems falling from the above. Then, saying it short, been there, was not impressed.