I bought DOBOT and Jetbot at the same time, and I have been using them for almost three months.
Here are my thoughts on these two products.

1- Yahboom's pre-sales and after-sales service are very good. I consulted emails three times before purchasing, and Dolphin gave a very detailed reply. After the purchase, the package was sent out in time, but the tracking number was changed once during the period, which is enough to show that the logistics company is too bad. Yahboom needs to switch to a better logistics company.

2- The appearance and structural design of the product are perfect, and there are almost no defects. But the materials used are not the best. For example: Jetbot's track, I have used it for so long and there are many signs of wear and tear, it is about to be scrapped. I paid over $500 for it, and I didn't just want to use it for three months. DOFBOT is not equipped with a battery pack, so I can only use it at home and cannot use it outdoors unless I have a large power bank.

3- Programs and tutorials are terrible. In the operating system provided by Yahboom, in addition to the codes required by the car and the robotic arm, there are also many unnecessary files, software packages, etc., which makes the image file too large and difficult to download from the Google network disk. I almost tried more than 10 times before successfully downloading the image file.

The tutorials they provided did not tell users how to implement certain functions in detail, but just placed screenshots of the program blindly. It took me a long time to implement all the functions one by one.

When I bought the robotic arm, I bought 3 additional steering gears as spare parts.
I hope they will never be used. Good luck to me.

This is a 6-DOF manipulator, and the quality of the steering gear looks very good.

I received my package the day before Christmas, which was delivered faster than I expected. Thank Yahboom for using DHL instead of some slower logistics companies.
The whole thing is assembled. I just installed the Jetson NANO board at my home, and the robot arm can work.

However, Yahboom does not provide batteries, which makes it impossible for me to use it outdoors. I plan to purchase a battery for this project.

This time I would like to give a fair feedback. A definite room for improvement by their international delivery partner here in NZ is needed thru a reliable track and trace system and "setting expected delivery delay times" (even on holidays).

Though, in terms of overall service, build, and quality… from Yahboom… the DOFBOT AI Vision Robotic Arm is such “topnotch educational product”. I have been enjoying and learning a lot of stuff with it at the moment. Just want to say, thank you for the great customer support and the great product! All the best!

I am an ultimate Nvidia user. I own almost all Nvidia boards, NANO, NX, TX2, AGX Xavier, etc.
This is my first programming robot. I have high expectations for it, and overall I am satisfied with this robot.
But it does have some shortcomings. For example, after controlling for a period of time, the wiring on the robotic arm may have poor contact. I have to re-plug the wiring between the servos to ensure the connection is stable, and then control. As mentioned in one of the comments, there is no battery in the kit and I can only use it at home, so it is unlikely that you will use it outdoors unless you have a power supply with sufficient voltage and current.
By the way, yahboom service is the best I have ever encountered. It's hard for me to believe that in this impatient society, I can get such a good service.