Milwaukee here. They have about 4 styles and some are available in different speeds. Some have a option to change the speed some don't.
Never tried the smallest one that fits in your palm.
The next size up is great for drillg up/down tight against the stud, is lighter, smaller, and good for work in finished walls. The speed is slower. The head can be rotated around which is nice. To change te speed if possable you have to take the head off (PITA). It will twist on you if it hits something but not too bad. The forward/reverse switch is too small.
Then the hole hog is biger, heavier, and faster. Dose not fit in tight places well but you still can drill a hole up/down close to a stud. I would not use it for much finished work. It will kick you. It seemed like the forward/reverse switch could be in a better place.
The best for roughing is the super hole hog. It's big & heavy but very fast. It makes the normal RA drill look like a toy. It is fast. Easy to change speeds and from forward to reverse. It is said to have a cluch to keep it from kicking back on low. I don't know because we don't use low much. I will say that the drill never kicked back on us once. One thing I hate is it will not get tight to the stud drilling up or down. If you drill the hole straight you will be about 1/2" off the stud.
WE use the super hole hog & the standard RA. Most our work is pipe so our holes are 1 1/8 - 1 1/4.
Tom
