Offset smoker with a vertical upright vs vertical upright on it's on?

Hey guys, was wondering yalls take on an offset smoker with a vertical upright on the other end vs having a separate vertical upright? I've always used my offset and vertical for different things, but I'm looking to have a new pit made (already picked my builder) with an offset and a vertical upright on the other end. I've thrown out the idea that I want a separate firebox dedicated to the upright and I want it to cook independently from the offset. Meaning I don't want heat or smoke from the offset to have any play in cooking my meat in the upright. I know having two fires might be a head ache... Aside from that, do you think this is overkill, waste of money, would appreciate any feedback or suggestions.