If it's a cash stay than I would opt for the PH and a Virtuoso booking as Pricesquire suggests... however if you're planning on doing a points booking, it is possible to book a club room at the GH (the PH does not have a club) using points...

I'm not an expert on Beijing geography (paging Moondog) but the GH and PH are in different parts of town. The GH is more in the Wangfujing district.. pretty touristy but pretty convenient to the tourist attractions. The PH is more towards the central business district (I think) so maybe not as convenient as the GH...

FDW