I've seen a lot of new 28 inch 4K displays. There is a 4K 28 inch panel that was made however, as of now, all the 28 inch 4K displays are the same TN panel.
You can enable HiDPI and have clear fonts but I recommend you don't but those panels, there is more to displays than resolution.
TN LCD panels usually suffer in contrast and color accuracy. IPS displays will give you a more vibrant and accurate color with deeper black levels. TN Panels do have better response time for gaming but if your looking for quality, I advise you stay away from those.
I advise you buy the dell or some other 30 inch 1600p IPS panel with wide gamut turned off unless you need to use it for photo editing.
Also check out this monitor: http://www.amazon.co...ords=lg 34 inch
It's a 3440x1440 monitor and is also IPS. However, it is slightly more expensive then the dell if you are willing to pay the extra money. It also has extremely light anti-glare coating, it could be considered as a "glossy" display as opposed to the dell which has pretty high anti glare coating.
It has more 1 million more pixels for more detail and sharper fonts then the dell but it is a very wide monitor if you think you would be fine with the very wide aspect ratio.