If you're looking for a glossy at the low end of the glossy spectrum, I would second Silver Rag. Very elegant surface, slight stipple. But it's latest incarnation is a little bit glossier and a little less stipply than before, and about 15 mils thick. I use it a lot, it looks terrific and is physically optimal for those of us who mount prints. Excellent gamut, you can get Velvia-like greens if you're not careful.
If you have a PK-only setup and you want the ultimate non-reflective surface, the Epson Hot or Cold Press papers soaks up light from any direction without a hint of reflection or hazing no matter where the light is coming from, and the prints are very rich looking for a matte paper. As mentioned, Epson used to publish PK versions of profiles for many of its matte papers, back in the non-switchable black ink days of the 9800 series. The penalty for PK on matte is longer drying time and perhaps a slightly raised d-max.