I.Know.GodI don't know why it says up to 27in, it really comes down to weight. I could mount a piece of cardboard 30" by 36" with VESA holes if I wanted to. The 34UM94 is 2.5 lbs below Ergotech's stated weight limit. I personally think it would work just fine with that monitor, the tension spring seems pretty sturdy. Obviously, the call is up to you.