It was handy a few weeks back when I bent a pipe that was in situ. Therefore I couldn't have got my benders on to it. With an external spring it wouldn't have been possible.
Therefore I suggest you buy some good quality Hilmore benders, and a cheap £2 internal spring from Toolstation.
i bought a pipe bender from b and q,, but i reckon it bends the pipe side ways a little.. i only use it for diy purpose's,, so i its not to much of a problem, but do hilmore bend pipe with out any twists?
think i wrote that a little bit wrong en.. what i ment to say was i bought the actual b&Q pipe bender,, i wish i spent a little more and bought the hilmore now,, but i think ill just use the 1 i got for now.. thanks
if you need to put a slight bend on an exsisting pipe then the external spring may help, i had one years ago and it worked fine aslong as you did not try to go to far with it.