Most of the machines, minus the Hitachi, have been around unchanged for some time now.
I've used the Milwaukee, Makita, DeWalt and a HF cheapie.
IMO the Milwaukee is a heavy old dinosaur, the DeWalt is LOUD and the Makita is a nice mix of weight and noise. Not the quietest or the lightest but it is neither loud nor heavy. All three are rock solid and will last for years with zero maintenance.
I'm a Makita fan. I have two 9227's and two BO6040's that have been used everyday for the last 4 years. Only thing I've ever had to do is change cords which I now do every year in my down time just to prevent....um... down time, haha!