They were purchased from a store that is not on the platform. As for the construction, it is sturdy and convenient for storage, meaning you don't need to remove them to put them in your bag.
The first drawback is that you have to open the front arms first and then the back ones.
The second and significant drawback is that the drone's inclination changes compared to the ground, making it lean more horizontally. I roughly measured that without the landing gear, it has an upward tilt of 15-16 degrees, while with the landing gear, it is 9-10 degrees. So when it tries to take off, it moves forward and the front propellers hit the ground, preventing it from taking off. You have to press the throttle very abruptly upwards.
In the Mini 2, it was much better designed and I didn't have such problems.