Do you mean reduced shank drills?
If so the drills depend on the quality of manufacture but at the end of the day even a good quality drill will burn the cutting edges if used at too high a speed so using a 25mm drill in a 1/2" chuck where the slowest speed is 800rpm is pointless (as your drill will soon be!).
Your better off investing in a mag drill and cutters or hole saws.
Depends on what you are drilling, as said the bigger the drill the slower you need to run it. If your just drilling thin material then step drills may be a better option.
They are best kept just for use in hand held drills. The forces involved mean they tend to slip In normsl 13 mm chucks. Of course you don't have the luxury of more taper drills out on site armed only with a hand held. Think I have 14mm - 24mm sizes in my box. Gotten me out of a fix a time or two but no good for serious work in the shop