One of the issues with SPR, though, is that they're small. It's well known that hatching pullet eggs often leads to small offspring. So, if you're hatching off a breed that there's no issues with size, it isn't a problem. Silkies being banties...wouldn't be much of an issue hatching small ones.
And from what I know of the Canadian Silkies, they're on the large size anyway, aren't they (most anyway)? I could be misinformed.
I had several with brassiness - unfortunately, it was the largest ones of the bunch. I recall wondering why that would be, and then got to wondering if they were all from one hen or something (Janet had told me that not all of her hens were laying when she collected for me, so it could be that the 3 males I culled for brassiness came from the same mother). I culled them all, keeping only the males without the brassiness. I have 4 now...I need to cull again very soon, hoping to keep the best two.