U3415W - best connection to PC? (mDP, DP, HDMI, MHL...)

I did a quick test based on the cables that came with monitor and ports available and compared mDP with HDMI. It looks about the same but I see the monitor runs at 60Hz on HDMI and only 50 Hz on mDP. I did try to manually set higher and it will not take unless I drop resolution.

So... how would you prioritize connections from best to worst?

I am not a gamer. I am a web designer and care about color accuracy and crispness of text display.

Thanks!