fredfinks :
Is the $741 27" worth it over the 32" samsung for $380? hell no, thats absurd. its a downgrade for twice the price.
In my opinion, your holding yourself back with monitor and a 1080ti. A 1070 would be enough to push that monitor.
There is a lot more to monitors than size and resolution. 10 years ago, everything was about size and resolution. While a 32" panel or larger may be great, it does depend on how close you are to the screen. 27" panels are considered large for PC gaming because generally you are sitting much closer to the screen.
There is a big difference between 60hz and 100hz. The difference is not as large between 100hz and 144hz. There is even a big difference between 60hz and 75hz.
The Samsung monitor that you highlighted is half the price of the PG27, but it has a 60hz refresh rate at 1440p with a VA panel. The comparable Asus/Acer panel will have variable refresh rate (gsync) IPS (much better colors and viewing angles) and a higher refresh rate.
It is not even close to a downgrade for twice the price. Seeing high refresh rate gaming at high resolution is something that you cannot unsee. Its like the first time you saw high definition. Pairing a 60hz/1440p monitor with a 1080ti is like getting a Ferrari and putting cheap gas and cheap tires on it.
I would also wait till you build the computer before the you get the monitor, especially if you want a ultrawide. High refresh rate, high resolution HDR monitors are coming this year. So if you want the best, they are coming. They will also set a new ceiling on the high end, making some of the current high end monitors cheaper.
HDR is fantastic, there is just not a lot of content. A lot of AAA games are being released with HDR support. If you put a 1080p panel with HDR and compared it to a 4k panel without HDR you would pick the 1080p as having the better picture.