I need to buy a new 4K (UHD) monitor. I will be using it for web/graphic design, general business, some 3D printing. It must have reasonably accurate colours. I shall NOT be using it for gaming. My budget is about GBP 600.

From reading reviews I have narrowed it down to:

A) Dell P2715Q – 27 inch £528.49 +£11.50 shipping from Scan)It is now slightly old as it was released 2+ years ago (Dec-2014?)
60Hz refresh rate, HDMI 1.4, DisplayPort 1.2a B) ViewSonic XG2700-4K – 27inch (£514.97 +£4.95 shipping from Laptops Direct) Released: April 2016?
Really designed for gaming but does that matter?
60Hz refresh rate, HDMI 2.0, DisplayPort 1.2a
FreeSync (max 40Hz) - but I won't use that

C) ViewSonic VP2780-4K – 27 inch (£591.22 from Amazon)
60Hz, IPS, 10bit, HDMI 2.0, DisplayPort 1.2a,
Released April 2015
Bluelight filter (to avoid eyestrain)

I definitely don't want ultra-wide. In fact I would prefer a "more square" taller screen than 4K proportions.

I shall probably use with on a NVIDIA GeForce GTX 1050 Ti 4GB Graphics Card (to which I could add another monitor later) connecting using a DisplayPort connection.

Any thoughts/other suggestions?