The 75U9G is a 75 inch 4K TV from Hisense, launched in the year 2021. It features a 10-bit IPS panel with Anti-glare/Matte finish. The max. resolution it can achieve is 3840 x 2160 @ 120 Hz with a pixel density of 59 ppi.
Picture Quality
After screen size and resolution, the very next specification of a display that defines picture quality is its Color Gamut.
Hisense has not provided a color gamut rating for this TV. But don't worry, we have other means to guess that. Considering the TV features amassive 75 inch screen, it won't come with a cheap panel, so here we can assume its equivalent sRGB coverage to be 90-100% or above. The color accuracy on this TV will be Lifelike! Meaning it is capable of producing accurate colors by default.
Understanding the Color Gamut Specification
Color gamut specification of a TV indicates the range of colors that it can produce.
In layman terms, this specification determines the ability of a TV to produce accurate colors. A display with low color gamut coverage will miss out on some colors (such as deep red), so the image produced will look "washed out" in colors.
Different manufacturers use different units to specify color gamut. Viz — sRGB, NTSC 1953, DCI P3 etc.
But don't worry, below is a chart that will help you choosing a TV with good color accuracy.
Now, after color gamut, you should look at the static contrast specification as it influences the picture quality the same way.
Understanding the static contrast specification
There are 2 types of contrast specifications for a TV. Static and Dynamic. We are interested in static contrast ratio as dynamic doesn't matter much.
This specification defines the intensity of black levels. That is, a TV with static contrast ratio less than 1000:1 will produce black images something like this:

Moreover, such TVs are also prone backlight bleeds that will rob your experience — as shown below.

Also note, static contrast ratio and resolution go hand in hand when it comes to details. To put it into perspective, a TV with low contrast ratio will produce less shades of colors, so lesser detail overall.
If given a choice, I will prefer a FHD TV with high contrast ratio over a 4K TV with low contrast ratio.
This TV is rated with a static contrast ratio of 8000:1., good enough to achieve deep blacks. The panel comes with local dimming feature which is a plus.
Dolby Vision, HDR10, HLG (Hybrid Log Gamma) and HDR10+ are also supported on this TV, so that's a plus.
As for brightness, it can go as bright as 1000 nits. The backlight used on the panel is Direct LED (Full-Array Local Dimming). This amount of brightness is good enough even for a room with sun's rays in!
Gaming Performance
Now if you are going to use the TV other than using it as a TV — say as a PC monitor or for gaming purposes, you should take a TV with lowest input lag. For gaming, both input lag and response time impacts the performance.
Sadly, we cannot find the input lag specification for this unit. But as this is not a cheap TV, we can expect an input lag of less than 20ms.
What is Input Lag and Why it matters ?
This lag is the latency at which your device inputs changes the content of your display. For casual Non-FPS games, input lag doesn't matter much.
For best of both worlds, get a TV that has an input lag and response time of < 20ms.
Ergonomics and Dimensions
Coming to ergonomics — VESA mount is supported on this TV with an interface size of 600 x 400 mm. Swivel, Tilt or Pivot features are not supported on this unit.
The width of this TV is 65.98 inches while its height is 42.83 inches. It is just 3.39 inches thick. Overall the TV weighs approximately 42.3 KGs including its stand. Without stand, it weighs 41.1 KGs.
Hardware and Audio
Speaking of OS, the Hisense 75U9G runs Android 10 Operating System.
For display connectivity, there are two HDMI 2.0 (b; ARC; CEC) ports, one AV Composite In (Video + L/R) port and two HDMI 2.1 ports on this TV.
USB ports include 1x USB 2.0 and 1x USB 3.0. Other connectivity ports include — 1x Cable/Antenna In (F-type) and 1x Ethernet RJ45.
Regarding wireless connections, you will have — a 5Ghz Wi-Fi, 2.5 Ghz Wi-Fi, Wifi-Direct and Bluetooth.
For audio, Hisense has provided 2 x 15W speakers on the 75U9G.
Now, coming to power consumption, it uses 240 Watts on average and 0.5 Watts on standby.
It supports a power outlet of 100 V - 120 V/50 Hz - 60 Hz.