It takes up to approx. 10 sec. before they are loaded completely.
The medium (and higher) res textures load in less than a second but add some significant noise to the frametimes which results in some kind of micro stuttering.
Processor Intel i7 5820k at 4.2 GHz
Board ASUS X99 deluxe
Memory G-Skill 4x 8Gb @ 2133 MHz
Graphics ASUS Strix OC 980 @SLI
Storage Samsung SSDs 850 pro
Monitor Benq UHD @60Hz