I have the M12/18 set of tools, really all impacts except one hex driver unit that can be used as a drill. I have a dewalt nano based drill,a nd I generally prefer corded where I can.
Is the fuel, brushless type necessary? I personally have never found brushes to be an issue, assuming they can be serviced.
The tools are strong and work well. If youre not going to be a heavy user, and don't have big concerns about runtime or absolute max power, the brush type tools may be somewhat cheaper and a better buy. That said, the M12/18 system should be out for a while, this sort of a form factor seems to be looking more and more like a rough industry standard design (until they decide they can implement planned obsolescence again), and there are lots of tools for this system.
Personally, Id go M12 brushed impact unless the brushless is not a lot more money, and then go M18 brushless 3/8 and 1/2 impact. That's what I have, BTW.