So is the easy way to spot selvedge is the single-line stitching on yours? Do all non-selvedge have this wide "ladder" stitching?
The easiest way to spot selvedge is the neat white trim, along with the redline/greenline/what have you running through it.
And not all non-selvedge has that stitching. Earnest Sewn, for example, has a two-color double-needle seam. A pair of cheap 517s I bought simply has two versions of PDC's outseam (don't know...