yeah i've seen and heard about them, heck I even have a set of SC springs that were heated to have a 4" drop, Would I put those on my cat? Hell no. The suspension isn't gonna be that great cause think about it, youre driving around with four springs that are already compressed, do you think they can be compressed any more when you really need that suspension like in a bumpy road, it ain't gonna be pretty.
If you're really looking for a cheap way to lower your car, cutting a coil from a spring is safer than heating them
oh and I would get the alignment checked afterwards just to be safe
friends don't let friends drive Chevy