I like the mc6000 as well. High quality mixer and product.
The problem with most modular setups is that they depend on the USB connection to work.
I personally have an X1 and Z1 that I use as my “backup” setup. There is no mic in for it, so I also travel with a small behringer mixer to handle my mics if my s4 decides to quit on me.
It really depends on how much redundancy you have and are looking for. I do mobile gigs with multiple laptops, so if one crashes, I can still use a different one. I also make sure I have 2 controllers as well as an iPhone that can play what I need if everything else fails.
With that being said, I like the modular setup. It allows me to have the bare minumum if needed, and it allows me to add what I need to it as I go.
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