It's competitive Turbine. Thus, it's Combine. If professional Viaduct can be called Product, then I say this pun is acceptable.
While playing Valve's Competitive Mode, I have suffered through more rounds of Turbine than I'm proud to admit. The design of the map is restrictive, in the way only an 11-year-old map can be.
So I've recreated Turbine from scratch, keeping the basic layout, (but admittedly, not much else) with modern TF2 map design theory in mind. Higher ceilings, larger doorways, shorter tunnels, and more options when pushing into and out of the map's chokes.