Several years ago I had D. tinctorius 'French Guiana' which were in a 50 gallon pentagonal tank. They would consistently climb around 2' up the tank. I would tend to say that the D. tinctorius would use it more than Mantellas, but I have read a few articles recently that some mantellas do climb more than we originally though. I must also admit the only experience I had with maintaining mantellas in the past was at a zoo.
I agree with Justin. I keep both tinctorius and a few species of mantellas and my tinctorius use the upper part of their terrarium more than any of my mantellas do. My male goldens will occasionally take a spot at the very top of their terrarium (about 16 inches up from the substrate) and call for a few hours but it doesn't happen daily. I've kept golden mantellas in terrariums that offer more height in the past but they just don't use it often and generally preffer to hang around little burrows or crevices down on the ground. My tinctorius on the other hand scale the walls of their enclosure daily, both the powder blues and dwarf French Guianas. Mantella laevigata is the one species of mantella that is considered at least partially arboreal and would use the higher areas in a terrarium often. Good luck,