The 50-inch smart LED TV of Dana model K-50GFBH has a 4k image resolution and its operating system is Android version 11. The viewing angle of this model is high and 178 degrees. The image brightness of the K-50GFBH model is high, 300-350 nits, and its contrast ratio is 4000:1. This model has WiFi and supports HDR, and its panel is VA technology.

In general, TVs smaller than 50 inch are ideal for a bedroom or kitchen. TVs between 50 and 65 inches are more suitable for the living room. And if you are looking to create a home cinema, screens of 70 inch and up are the ideal choice.
You have said 2 TVs which are identical in every respect, calibrated the same, only difference being one is 50″ and one is 55″. There won't be any perceived difference in PQ. The pixel size in 55″ is larger but sitting at standard 6–8 feet viewing distance, you will not see it.
So in summary, a typical 55-inch TV is about 48 inches (121.9 cm) wide and 27 inches (68.6 cm) tall, with a diagonal screen size of 55 inches (139.7 cm).