I think soil is pretty bad.
Most plants will not grow because the light level is too low. Soil holds moisture and is a reservoir of opportunistic microorganisms that may infect the snakes. I don't think that soil can handle the unscooped portion of the waste. Some snakes will root around and disturb the soil besides crawling over and damaging plants unless the plants are large and sturdy.
On the other hand, some of the European herpers are supposed to be doing good things with naturalistic setups, but I don't know the details.
I have a vague recollection that Neodesha went out of business some years ago. I didn't pay much attention because I don't like sliding doors, which was the only type that they made.
Vision and Boaphile plastic cages are supposed to be pretty good, though I've never used either. I lean towards the Habitat Systems Limited cages.
Paul Hollander
Habitat Systems Limited web site