I’ve done some cool heraldry for my RR with color changing. The issue is not waste it’s just usually too time consuming for production needs. We often work under very tight deadlines and it’s faster and usually prettier a result to hand the prints off to the paint department.
But the .02 nozzle and some color changing can yield neat results.
Edit: some examples
Another use for AMS is to use water-soluable filament for your supports.
You sound like my ex wife!
I report anything Amtrak to the site owner.
To close this out, I’ve watched or read a number of comparisons & reviews on Bamboo Lab’s latest mid-range unit, the P2S, vs. Anycubic Kobra S1, Elegoo’s Centauri, and Bamboo’s X1C.
Based on all the inputs I went with the P2S. Seems nearly as good as the X1C, with newer tech in some ways, and slightly lower in cost. And without the (purported) headaches of the other two brands, which many have remarked on.
I heard it opined that the X1C would be upgraded as well soon, but it’ll be out of my price range. And, I’m getting my annual Christmas+birthday spousal discount, so needed to decide. 
I’m really looking forward to printing with ASA, without fuss, for outdoor parts. Some of my structures have PLA parts; but despite multiple spray paint layers, they’re crumbling. Those can soon be upgraded.
I might upgrade my printer for the heck of it. Something with a larger bed.
