The first cordless tool I bought was the Milwaukee impact driver above, and I bought it because at the shop where I was working, everyone was using Milwaukee and I had seen how much abuse they took. Now 10 years later, I've stuck with Milwaukee because I don't want more than one battery platform, but also because the tools have been great and Milwaukee is constantly coming out with new stuff for the existing battery platform, as well as improving the batteries themselves. The new M18 Forge batteries are supposed to be killer. Additionally, if you watch Torque Test Channel on YouTube, Milwaukee consistently ranks at or near the top of their fairly scientific tests.
If you've already committed to one of the other big brands, I wouldn't switch, but if you are just starting to build your toolbox or your old NiMH battery tools are finally shot, a Milwaukee M18 drill/driver combo set is a solid starting point to build off of.