C520 What navigation map do I use? How is the quality?

Pre-installed the latest mainland standard version of electronic navigation map, high-sensitivity GPS receiving module to quickly locate, and create an efficient business navigation engine. It is equipped with a brand-new 3D enlarged view of the intersection, original direction signs, service area-specific tips, lane turning information indicator lights, and the navigation process is clear at a glance. Weekly updated DSA alarm point data makes your business trip safe and convenient. C520E contains information about tourist attractions, shopping, food and so on all over the country. Support photo album browsing, exchange rate and unit conversion, world time, calculator and other tools. It is your intimate travel assistant, adding a lot of fun to the monotonous driving life. C520E function: 5-inch screen+brand new 3D navigation map with 4D map +4G storage space, support external SD card +CMMB digital TV, radar mobile speed measurement, fixed speed measurement early warning system, MP3 music, MP4 video, picture browsing, e-book function+digital navigation, quick spelling query, and handwritten input to query destination. The whole machine has a one-year warranty, three years of free TV watching, and then give me a free upgrade. Let me swim C520E, and use four-dimensional map to navigate the new 3D map. The quality is quite good and is well received by consumers. Let's take a look at the consumer's comments on this machine: Advantages of high-definition 5-inch large screen: C520E was built by myself, not by myself. I will only know it when I ask the customer service. Disadvantages: I prefer Khalid map, which I can use. Summary: The interface is a little unaccustomed, which is very different from my previous freelancer. C520E has many advantages: many functions, and the price is not cheap. Disadvantages: I used it for a while and found no problems. Summary: It's good to use! Let me swim C520E. Disadvantages: the screen is not large, and it is suggested that the price can be higher. Summary: The picture is quite detailed, but it is still satisfactory. C520E is a professional flagship product of inter-city safety early warning service, which adopts the leading integrated design of fixed flow and speed measurement. 5-inch large screen, full of textured streamlined wing outline, and high-strength wear-resistant material on the back, which presents a matte texture through careful construction. On the whole, its appearance has a strong business element, showing a noble atmosphere. C520E is pre-installed with the latest mainland standard version of electronic navigation map, which has a unique mobile speed measurement function. It adopts VCO high-sensitivity full-band scanning technology, adjusts the sampling monitoring frequency band in time according to the police radar frequency band, displays it on the navigation screen and voice prompt, and perfectly integrates with navigation software to realize the effect of intelligent monitoring system. In addition, it also has a brand-new 3D enlarged view of the intersection scene, original direction signs, service area-specific tips and lane turning information indicator, thus realizing an efficient business navigation engine, which can fully meet the advanced needs of China car owners. For example, self-built waypoints, route planning, arbitrary choice of avoiding roads, number navigation, emergency inquiry and audio-visual functions can also be easily realized.