It really depends on the space that you have in your home.
The foldable legs are very convenient because they allow you to store away your bellicon quickly and easily. So if you have a smaller space, or you plan to store it away when not in use, the folding legs are a must-have.
But, if you plan to keep your bellicon set up in one spot, and rarely move it from the ready position, the screw-in legs would be a great option. If you have the space, it is always best to put the bellicon in a place where it is ready to use and very visible. This will help to encourage you to use it often. Remember: out of sight, out of mind!
Both type of legs are equally durable/sturdy and carry the same warranty.