Hello. I'm happy to answer your questions. For beginners and novices, the overall situation is the same. The quality and handling performance of the three cars in the same price range are similar. Key points: 1. Warranty and after-sales service should be convenient. Avoid online shopping. Which store or stores are there nearby? Check the service attitude and buy in the store. Read the warranty provisions in the product manual clearly. The thicker the accessories, the different the warranty period. If you don’t understand, ask the seller, because the warranty for wearable parts such as pedals and tires is very short or even non-guaranteed (for example, if you get a puncture). 2. Choose the right frame size. Cycling is the same as regular exercise. The style and size of clothes and shoes must be appropriate (for example, running with a size 41 foot wearing size 40 or 42 shoes will eventually cause problems). In this regard, I recommend Giant or Global UCC, because each of these two, especially the former, has a "frame (product) geometry diagram". Merida rarely provides frame geometry diagrams for domestic sales, and can only rely on sellers’ suggestions (because there have been examples of recommending small-size bikes to tall people in order to reduce inventory or make more profits). As shown below, Giant, there is a height and frame size corresponding table in the picture for selection (this table shall prevail, don’t just listen to what the seller says). 3. If your height is "cross-border, one side is small", such as 164cm, then in the picture above, both XS and S sizes are acceptable. It is recommended to test ride both, because everyone's arm length and shoulder width are different. XS code, as long as the upper body does not feel "nested" when riding, the control performance is better and more flexible, while S code is good for pedaling force, speed, high-speed cruising and climbing. 4. Confirm with the store manager in advance: when picking up the car, whether the brakes can be adjusted properly (without disc friction), the gear shifting (when shifting gears, there is no obvious scratching sound or hesitation and slowness between the chain, flywheel and chainring), and the height of the seat cushion Adjust properly (involving pedaling force, psoas muscles, and knee protection). New cars are all tuned, but some are handled carelessly, so you need to make it clear in advance. 5. If you are considering upgrading some high-end accessories as needed in the future: Giant is recommended. Its ALUXX SL (that is, the ultra-light ALUXX manufactured by Huigao Aluminum) aluminum frame is well-known in the industry (Giant holds international aluminum first-line factory Huigao), such as the top-level FOX SC 32 FIT4 Kashima version with front fork replaced by XC type (￥5 More than 1,000), 4,000 to 5,000 famous brand national carbon self-made wheelsets, this frame is worthy of it and will not be out of date. Secondly, Global UCC, because it is OEMed by Kinesis (this is one of the first-tier OEMs in Baodao, and its patented SPF aluminum technology is better than Merida's HFS or hydraulic aluminum technology that has not been updated for several years). This can be ignored unless you consider high-end upgrades. 6. If you consider that second-hand products can retain more value in the future: Giant is the first, followed by Merida, and UCC is at the bottom. Everyone knows the brand effect. For example, second-hand cars of the same grade, such as Mercedes-Benz, Volkswagen and BYD, are easier to sell. 7. Configuration issues: Beginners don’t need to worry, all three are the same. At most, the gear kits are one level higher or lower, but they are all Shimano's professional grade. The key is to have someone adjust them and maintain them regularly yourself. Take Shimano as an example, the entry-level 10-speed deore in 2013