Nylon or any other kind of semi flexible pushrod has to be properly supported. I use Sullivan
Semi flexible carbon fiber pusrods in my Tiger 60 and Golden rod Nylon in my Tiger 2
I brace the outer shield every 4 inches to keep it from flexing under load. also I
let the outer shield stick out of the fuse a few inches at the tail.

Problem I see is that I built mine from a kit so bracing was easy before covering.
Sig is a good manufacturer and I think they would brace the pushrods pretty well.

Also instead of insering the small threaded end into just the tip of the pusrod get a long piece
of 2-56 pushrod that is only threaded at the end, Install this pushrod a few inches into the flexible
pushrod and glue.

In my picture you can see the metal pusrod is inserted into inner rod past the point where it goes into the
outershield. which I never cut off. It is very strong and doesn't flex.