Agree and disagree. Red River paper is not "exceptional" quality. Exceptional is defined as being "unusually excellent" and I have had a few minor quality control issues with RR paper.
But it is very good quality for the price. Exceptional is Hahnemuhle and/or other fine art papers.
However, I will say that I began using Polar 2.0 as a replacement for Gallerie smooth pearl. I no longer buy the Ilford product. Polar is equal to and often surpasses smooth pearl, but is lower cost.
A note about the RR metallic. It is about the best you can buy for home printing. However, it doesn't come close to the metallic appearance you get with metallic prints from mpix. Depending upon the image, the RR metallic can almost look like normal paper and even when you "catch the light right," has a low metallic appearance.
As a general catch-all evaluation, I would say that Red River paper is a good choice for high production print applications, but for gallery or museum purposes, I would choose other fine art papers.