The Rio should work fine. I use a loop-to-loop for the tippet piece, and it works reasonably well. The knotting problem is not an issue if you tie knots CAREFULLY, as you should anyway. Wet the knot before pulling tight, and pull slowly. Heat buildup from friction is what kills knots in fluoro.

As for brand preference, people like what they like, and no amount of data will alter some people's minds. You will find one that you like, and that will be good enough.

Dennis