Yes, the Bedair SS guide rod will work with the factory spring, but I changed mine to a Wolff spring. I've also installed a buffer for GP's with no issues.
I'm running the Bedair SSGR, but have only done about 50 rounds with it. I didn't see any wear, but 50 isn't much. It's hard to say what would be causing the wear, but I'm not sure it's the spring. The spring never comes into contact with the area that seems to be affected. Also, it's hard to tell by the pictures, but it almost seems like the edges are the parts being worn. That doesn't seem possible without the GR pivoting and wearing in other areas more. The GR fits into the channel and really doesn't move all that much and remains relatively straight. It would be nice if there were pictures of before and after several thousand rounds with the SS GR.
Another post mentioned that if there were this much wear between a hard and soft object, if the plastic guide rod were being used, wouldn't it be the one to wear out? That doesn't seem to happen though.