I’m using the LoNoiz .130-Inch-by-150-Foot Spool Commercial Grade Spiral Twist Quiet 1-Pound Grass Trimmer Line, Black LN130DLG-12
https://www.amazon.com/gp/product/B000E2D3DU/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1
It’s fantastic, except it does fray at the ends after awhile. So it occurred to me that maybe I should try the old nylon rope trick of melting the ends shut using a lighter. Did that yesterday. Now comes the test!