They really are.
The MK3 is an absolute beast of a workhorse. We use two MK3s at the lab I work at. They collectively have 2000 hours of print time and they just now started exhibiting issues. One had a hotend fail, the other had a thermistor fail.
They're damn good printers. I heard bad things about the MMU2, but I'm hopeful the MMU3 will be great, I have one on preorder.
I'd look into the nextruder upgrade for your MK3, it's really nice. Only two thumbscrews to release the hot end out, and the LoveBoard makes servicing different components on the extruder a lot more painless.