I don't think you can go wrong with any of the three honestly. Makita's 18v tools have been really really good and have held up to just as much hard use as any Dewalt I have owned. The only thing about Dewalt is they have service centers around where you can get the tools fixed. That has always been the reason I have used mostly Dewalt. If you really use them you are going to need a service center. If you aren't using them that much buy the best deal and go with it.

Dewalt and Makita's electic impact drivers have been a life changing experience. I am not sure which models we've got but I also have probably the best Snap-On air impact money can buy and I would say these are nearly as good. Working on something without a service truck with onboard air...... a 1/2 inch electric impact is a life changing experience. I think they both have breakaway torque over 1k ft. lbs. and they deliver.