The Good: Great picture quality, attractive design, great build quality, low blur, low input lag.
The Bad: Narrow contrast range, washed out dark colors.
The Verdict: While the issue with darker tones can definitely become annoying, it's about the only significant flaw this TV has. Being priced significantly lower than the competition compensates for that flaw to a certain extent.
Samsung UN55JU6400 is a TV that generally features a good performance, minus some flaws that may, or may not impact the overall experience. It is however noticeably cheaper than the competition, especially with the set of features like this.
Samsung UN55JU6400 sports a very attractive design with its thin bezels, and brushed steel texture. It looks and feels like a more expensive product. The stand is rigid, but rather small for a TV of this size. However, it provides sufficient stability. The speakers that come with Samsung UN55JU6400 are loud, and offer a good enough definition to be used regularly. The side panel sports 3 HDMI, 2 USB, and one RF port, while the rear panel comes with an Ethernet port, 1 Composite In, 1 Component In, 1 Digital Audio Out Optical, and a 3.5mm Audio out.
Samsung UN55JU6400's performance is mainly hindered by its very narrow color gamut. Not only does it need calibration right out of the box, but even with proper setup, darker colors are going to appear washed out. Most noticeably, black is going to be closer to gray, which can limit your movie watching experience to a certain extent. At 4k, the picture is great. Samsung UN55JU6400 upscales very well in just about any resolution. There is almost no blur on this TV, and the transitions are smooth. Number of apps supported by this TV's operating system is very limited. However the software is easy to navigate, mostly thanks to its clean layout.
If you can excuse the washed out dark colors that are most noticeable when you are watching this TV in a poorly lit room, Samsung UN55JU6400 is otherwise a great performing budget 4k TV. Low amounts of blur and low input lag make it perfect for gaming, while it also excels in almost any application. For the money, you will be hard pressed to find a better deal.