Yeah except having to navigate between the two can be tricky. Also that means we have multiple dynamos and multiple cognitos (in our case, test and prod), which is a pain.

I use Firefox for the prod console and Chrome for the test console. Obviously that system doesn't scale past 3-4 accounts. ;)

I would say that once you get beyond those additional two-three accounts, you have tackled the mess and scaling to 1500 gets easier. And yes it's mind blowing.