My 2 cents: while on the phone with Kel Tec for some other issues, I mentioned that both my inner and outer springs were bent. They sent me free replacements. After shooting 50 rounds with the new springs, I noticed the inner spring is bent again. None of this seemed to make any difference, so I've concluded the bending is perfectly normal. I figure the guide rod is holding them straight anyway.
I called Kel-tec. They sent me new ones free. They said that they will eventually fail. I'm not worried about it. It seems normal. I figure that I will keep an eye on it and when they start to look worn I will replace them.
when you have the springs in the barrel/slide assembly, rotate the outer spring to besure it is not interleafed with the inner. this should ensure that the end coils are resting solidly against the slide and recoil rod head. once a spring has taken a bend, it MAY become selective about orientation when installed, thus try to replace the same direction or at least "feel" as you slowly rack the slide for any jumping of coils