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Good idea, I think that the current design (although beautiful) could use up more data than it needs to. That could be a problem for mobile players.
It might be a good idea to automatically load the lower-quality/feature-reduced site for mobiles, with a prompt mentioning a higher quality version is available.
I personally haven't experienced any issues with data on my device, seems like BitKong is mostly cached, so doesn't need to be loaded from scratch every time.