my cards have only 2 dp ports, i have a hub on both.
the startech DisplayPort to Dual HDMI Multi Monitor Adapter M/F - DP to 2x HDMI 3840x1200 is the one i got.
running 3 monitors you should be good with 1 of the hubs i got, and 1 dp to hdmi, if all your monitors have hdmi.
one of your dp ports on your card would run 2 monitors through the hub, the other dp should run the third monitor with the adaptor you linked.
the hub i got acts as both the mst splitter, and the dp to hdmi output in 1 box.
you want to run all your monitors out of the display ports. i don't think the transition of 1.2 input to 1.1 output on the hub matters much.
if you went with the 2 hdmi output one i went with, then added a displayport to hdmi on the other dp on your card i think it would work quite well.