Have you considered adding compatibility for Bob's Logistics and other mods that modify the belt tiers? No worries if you don't want to. :D

It's compatible with the Double Speed Belts, the express belt will be twice faster than the red one.

It seems that the mod breaks when using belt-layer.

Have you considered adding compatibility for Bob's Logistics and other mods that modify the belt tiers? No worries if you don't want to. :D

If you want higher speed to match the high tier belt in bob's mod you can add lines of code to all *-belt.lue in prototypes.

under this
if mods["DoubleSpeedBelts"] then
speeds["express-linked-belt"]=4*0.03125
end

you must add
if mods["boblogistics"] then
speeds["express-linked-belt"]=5*0.03125
end

final look:
if mods["DoubleSpeedBelts"] then
speeds["express-linked-belt"]=4*0.03125
end

if mods["boblogistics"] then
speeds["express-linked-belt"]=5*0.03125
end