I have a 12 year old ludisia discolor that is in potting soil. In fact I've never repotted it. It's an office plant and gets watered once a week if I remember. It blooms faithfully every year. It's sitting atop a bookcase next to a west facing window. I just cut off 6 finished spikes. Mine has developed a trailing habit, and I'm not sure if that's due to it's age or culture.

It has pretty much taken over the entire top of the bookcase ala Wandering Jew. Anyway, it's doing well so I'm not going to mess with success.
BTW, I have given cuttings of this plant to several people who have had good success rooting the cuttings.