By no means am I about to criticize Rio lines. I have and use many of them and buy a lot of lines every year. Rio is perhaps the most castable line for newer folks. By making their lines a half-weight heavier than standard they slow the action down and reduce timing criticality. They cast easier.

I have rods that respond very well to over-weighting and some to under-weighting. My wife hates her 5wt Sage until she uses a 7wt TT line on it. She likes to roll cast.

There is nothing like actually trying various lines on a particular rod to see what feels best for you. Not everyone is trying to cast across the Great Lakes every time out.

At a Denny Rickards seminar a month or so ago he stated SA makes the best lines, period. Of course he only fishes lakes and finds the intermediate sink rate lines by SA to be exactly the right thing for him.

Everybody is different and every rod just complicates that issue.
art