AFAIK there's no master thread for this place yet, as the property is fairly new. It's located in a modern building right next to the Rondo Daszynskiego metro station, and is very well situated for business travel as this area is probably the most dynamic in terms of new businesses relocating here (the traditional business district is known jokingly as Mordor as it's a lot less pleasant).

Since I'm doing the Diamond Challenge, I decided to try one night here. This is not really intended as a proper review but I have to have say I was impressed with the general look and feel of the place. There is a bar next to reception (Signature Bar) and a decent restaurant on the First Floor (Nova Wola) that is also used for breakfast (which was also decent btw).
There are 6 lifts right next to each other which are all really fast. I can barely remember ever waiting more than around 15 seconds for a lift.

On the 21st floor is the rooftop bar, also known as Sky Bar, which is a great place to hang out and observe the sunset - you'll only see this view in the summer, when the sun is far enough north to be visible from the Sky Bar. But at least for now it's well worth taking advantage of and many people there were standing by the glass taking photos. It's actually much better than the Marriott Sky Bar (40th floor) because the Marriott bar only faces east, so no sunset views and the windows seem darkened and dirtied with age.

I didn't get round to seeing the lounge as I didn't get access as a Plat, but all the staff I spoke to said I would have comped access to Club as a Diamond.

However, when visiting the HIX last week (in the same building) the FD person I spoke to said that the CP GM (Marcin Szufel, who's also GM of the HIX in the same building) intended to revoke Club access to Diamonds once he returned from vacation. She explained that since Diamonds were now getting free breakfast as an amenity, he would take away Club to even things out.

This seems like a really backward step to me, as well as being petty. I don't know if it's actually going to happen but if it does it would be a real shame and reflect poorly on the GM. Club access is worth more than breakfast to most people and this kind of move reminds me of the worst aspects of the old IHG program, where GM's would often do anything to sidestep giving genuine benefits to people with top status. Even under the old program, top tier (Spire) tended to get you lounge access at most CP properties.

Once I'm made up to Diamond I'll go back and talk to staff and see how things stand. If it's true that the GM revokes Club for Diamonds, then I'll probably put this place on my avoid list, which is a shame because I really like this place and think that it's a great option for people in WAW.

PS I'll some pics if I get time over the weekend