There’s nothing wrong with going back to old hand tools that were made when James K. Polk was in the White House. Who needs a DeWalt when you’ve got a hand drill?
Going to work on cars? Milwaukee. Not going to work on cars? Can save a few bucks with Dewalt, the nailguns and saws are real nice. I say this as someone who has a LOT of Ryobi but they just don’t work as well as the better stuff. If I had either of the two big brands I could probably ditch my corded circular, jig and reciprocating saws. Same with the 4in grinder.
Hand tools just mix and match, they don’t need to be the same brand.
Power tool batteries are expensive and are not interchangeable between brands (without 3rd party adapters that can be a bit risky). I only own DeWalt power tools because I want one set of batteries and chargers.
I have no brand loyalty to hand tools, however. Well, except for Knipex. My pliers-wrench has been life changing.
