Do you know what type of Den you have? Can you post a photo? It is most likely a Den-Phal type, or possibly nobile type.
Yes, they will have finer roots than a Phal.
For Den-phals, media should approach dry before watering, but shouldn't be allowed to remain dry.
Nobile types like to remain lightly moist while growing in the spring, summer - but need a dry (no fert, bright and cool) rest in winter in order to bloom. Not giving the rest won't harm the plant, but it won't bloom the following spring, and probably make lots of keikis instead