The choice of machine is just that, a choice. It offers alternatives and differing paths along the journey. I'm in no doubt that I could have an acceptable journey along the path of single-boiler machines with temperature control, or with a heat exchanger machine. I looked at the options, what resources I've been blessed with, and chose the Vibiemme double based on what I thought gave me the best long-term path to travel.
I'd venture to say even in 3 months I've but taken a few feeble steps on that path, and stand humbled before the masses of those further along the journey with what some would call simpler machines.
It's a machine, merely a tool outlining a path (or John's river) to travel, nothing more, nothing less.