The best denim maxi skirt is the one that is made for you, to your specifications and measurements, from a denim of your choice. (I would go medium to heavy weight, with medium being the preferred fabric.) Of course, it won’t be as cheap as some of those mentioned, but it will last you much longer, probably a lifetime unless you wear it every day (in which case, you might want two) and bring you satisfaction every time you wear it.
To avoid a split, you’ll want a stretch denim, or possibly an ordinary denim cut on the bias.
Cut on the grain, you will end up with a stretch skirt that might need a little split somewhere (back, side, both sides) for movement. Alternatively, a bias cut in denim will have both vertical and horizontal stretch. It will fit your form naturally as it falls from the waistband as the widthway stretch accommodates you hips & bottom and skims slightly inwards from your thighs without being restricting. In production, the skirt is left to hang, unhemmed, for a period of time to allow the fabric to drop to wherever it wants to drop before it is hemmed, and the hem will have a slight, natural ripple and space for you to walk without the need of a split. I had such a skirt once, before I passed it onto a friend. It was gorgeous.
Let me know if you want more details.