I know this will be fraught with opinion, that's what I am looking for.
Under 50.00, you ask? Yes, that is the budget..hopefully under 40.00...and why, you ask?
I treat my gear pretty rough, especially line...gear stays in car, line on the rod, stepped on, dragged through mud...you get it, I use my stuff and use it a LOT many weeks the line simply stays damp.
Thinking on Cortland 333 or 444...saw some sales on those, Orvis Silver and a couple of Sci. AM. lines look OK.
I like a fairly slick line and very limp...hate a stiff line.
My current favorite is a Cortland Wind Taper...actually got 2.5 seasons out of it...but it is time.
Yes, I do get cheepie seconds but for my 6 wt. I want a better line.