Ellis, I've been using Silver Rag since it's introduction (I was a beta tester of the paper back when i used the Epson 4000). I also have the Canon iPF6100, and I really love the paper with the Canon printer. I print a lot of B&W, and it's always very neutral with slightly creamy highlights, since the paper is not a "bright white".
I keep trying other "photo rag" papers, but am never as happy with the end product as I am with Silver Rag. To my eye, it still looks the most like a silver geletin print when it comes out. Color printing is equally appealing. I've used Canon's Polished Rag and heard the same thing, that it's basically Silver Rag rebranded. The main difference seems to be the profiles provided by each manufacturer, which yields ever so slightly different results.
It's a great paper. The only neagtive is that it can sometimes have a rather strong curl to it, so you need to boost the vacuum.
Nemo