Just now I went up the new HDB at 810am that's beside Greenwich, to take a nice bird eye view. I've really nothing better to do I guess.
I went to the 23rd floor, highest floor. The view was really spectacular. I could see all the way to CBD. I took a few pics of the nice views.
But... It was like wow, constant road sounds, and especially loud sounds from certain motorcycles, buses and noisiest of all, rubbish trucks. There was a constant droning sound from the road.
I decided to move to the 11th floor, which is nearer to the 11th floor of Parc Greenwich. Take note the land of this HDB is about 1 floor higher up, that's why it's comparable.
Wow, the noise on the 11th floor is quite bad. The view, while good, is also not as spectacular. Pretty standard.
My conclusion is that the unblocked view was overhyped. It now makes sense why the psf of the road facing units are lower.