Seems strange to me that a lightning fast tool change is needed on a manual machine like a Bridgeport. Does that mean after the lightning fast tool change you crank the handles at lightning fast speeds?
I can only speak for myself- but I only get paid when the spindle is turning, and the parts are in print.
A power drawbar changes the way you use the machine. It's usually faster to put and take a part in the vise than to manually change tools. A power drawbar alters that equation, which translates to fewer part changes.
When you are using multiple tools on location- center drill, drill, tap. Keyless chuck- load center drill all the way up in the chuck. Set the depth stop for the chamfer, center drill. Change to the tap drill- it's longer than the CD, so I can drill thru without moving the quill stop. Change to the tap in a keyed chuck- it's longer too, so just power tap the hole. 2 tool changes per hole. Over a run of 500 or 1000 holes, that adds up.
Faster to tap a hole on the VMC, but not every part fits on the VMC.
I make a handle where the distance from a hole pattern to the end of the handle has to be held fairly close. The part does not have a good repeatable locating surface. So the part goes in, the end is machined, then I crank over to the holes and change the tool. I make both features in one clamping, so the distance from the end of the part and the hole pattern is consistent. If I was manually changing tools, I would probably put and take the part- mill all the ends, then drill all the holes. I would have more difficulty holding the tolerance due to the loading error.
Like my first example, that also would be faster on the VMC, but the part doesn't fit on the VMC- one end has to hang underneath the table.
It also takes away some of the temptation to be lazy. Say a counterbored hole- I know it's a no-no, but I might be tempted to stick a small end mill in the drill chuck to cut the c'bore. If I have an endmill or c'bore in a holder sitting there, it's just as fast to change the tool and do it right...