This mod adds an additional five tiers of belts to the game, beyond what is currently available from other mods. The fastest belt in this mod is equivalent to 6 express belts.
I'm glad you like it! :) If it's not too hard to implement, I'll make the underground distance configurable. Right now its hard-coded to +5 per tier, but if I can make it configurable then each tier can increase the underground distance by however much you like
