Springnet Underground

Does anyone have any experience with the Springnet Underground in Springfield, MO?

In case people don't know it's a working limestone mine. In the areas that have already been mined close to the entrance, they've sold or rented out space between the rock pillars that hold up the mine roof. The city of Springfield put in a data center and started selling services out of it that complimented their city-wide fiber plant.

They've been suggested as a site for hosting a cabinet full of gear. I'm wondering what the connectivity options are for that facility and so far haven't been able to get a straight answer from anyone. For the most part it looks like the SprintNet folks want to sell you their own upstream which won't cut it for our needs. AT&T serves the area of course but I will not have them as my last mile (or any mile for that matter). Does L3 or any other large carrier have facilities there? Does anyone have any experience with the facility in general?