I was impressed by the Milwaukee. I've got a Makita 18V that is about 10 years old. Very few options back then, also very expensive back then, about $350 for tool, battery and charger, and I was surprised by how poorly the Makita did against the competition - it appeared to be fairly average for speed of cut.
I've bought into the Makita 18V eco-system, so I'm not changing, but if I were shopping multi-tool today - it would be the Milwaukee, hands down.