I just got this router. It seems to be working well, well better than the Shaw one I sent back. I haven't had good luck with refurbished products in the past but this has good reviews. It has a guest network but not sure if it's to your specs. I don't need it and so disabled it. They also have the original new router for $170.
http://ncix.com/products/?sku=73594&...s&promoid=1479