Also, depends on your budget, you can get a Dell Precision M3800 that has QHD+ 3200 x 1800 resolution. I guessing it will not be long before others in the range will offer that resolution or better.
I had one of these before I moved to my job at Samsung. It was an awesome machine. It was an i7, 16GB ram 256 Gig SSD and 500GB spinner with an Nvidia Keppler GPU and Intel GFX chip running win 8.1. Fastest machine i ever had. I miss it terribly.