Sydfly not a problem answering questions. The internet appears to be free (so far at least!) so happy to help.
The rooms are very nice and the photos probably don't do them justice. Three of our four nights are on points and were booked at category 5 level. For 12,000 points I am very happy, but probably wouldn't feel I had great value at a category 6 redemption level to be honest. I think what sets it apart from say a really good category 5 hotel (I'm thinking Westin Bund as we stayed there last week) is the overall hotel experience. It is hard to put my finger on, but the place just feels like a luxury hotel rather than a great business hotel. The butler service and attention to detail is also very high. To be fair we chose to stay here for the experience of it rather than for the greatest rooms on our trip. You do feel special staying here, so from that aspect it succeeds. However if I was in Beijing again I would stay at another Starwood property just because we would have had the St Regis experience.
The bathroom amenities are by Ashford & Hall and seem ok, but nothing special to be honest. The bathrooms are well kitted out with extras and we found the bathroom TV in our room as well now.
The Diplomat Deluxe room is very nice and has enough space to be comfortable in. We have been told that many of the superior category suites are on the higher floors which are still being renovated, but they should be opened up in the next week or so meaning you may have the chance of a nice upgrade. However this is still a very nice room standard.
We did a quick wander by to the Apartment block which houses the gym, pool, spa and bowling lanes. (The bowling lanes are closed at the moment though.) The pool is open 24 hours a day and they do apparently have some hot springs, but we haven't checked them out yet, but we will hopefully have a look tomorrow at some point.
I can't compare with the Westin or Intercontinental in Beijing, so have no opinion on which is best. For the experience the St Regis scores well. However like for like with regards to rooms, I suspect it is on a par at very best with the competition.